Home » Digital Marketing » Everything You Need to Know about SEM in 10 Mins

This vlog will give you an overview and all the basic information you need to know about SEM in 10 minutes:

– What is the definition of SEM? What are SEM and Paid Search?

– How does SEM work?

– What factors affect the effectiveness of a SEM campaign?

Let’s answer all these questions in the 3rd vlog.

Below is the text version of the content in the video:

SEM, also known as Paid Search, is one of the most effective advertising channels that many businesses now use to reach customers; and one of the main channels that help them sell more.

SEM is also a channel that for many businesses is the mainstream channel, which accounts for most of the budget of advertising.

Today we would like to help new SEM beginners learn about SEM and Paid Search and have a  quick grasp of what it is. What are the components? Where does it appear? And more importantly, what factors affect the effectiveness of a SEM campaign?

SEM stands for Search Engine Marketing. Search Engine Marketing is the marketing of advertising on search engines. Search engines can be Google, Yahoo, Bing etc.

SEM was once understood to include Paid Search + SEO. Later, people gradually follow the Google way of calling it, with which Google wants to lead the user to refer SEM as paying Google ads, not SEO. Therefore gradually SEM is mostly refered to Paid Search. Today, we see that people like to call SEM and SEO as two separate things.


When you go to Google to search for any keyword, you will often see that the first 1-4 results will be the Paid Results (TOP); The last 1-3 results of the first page are also the Paid Results (Other); previously, there were side-columned paid results that Google later abandon; In the middle there are 5 to 10 results that are not paid – Organic Results. Organic Results – The natural result of SEO. The top and bottom paid results belong to SEM

Paid results are almost no different from the natural results except for the addition of the “ads: text next to the ad results, and it will also include extensions like a phone number, address, sitelink, callout of that business. These add-ons help the paid results stand out comparing to the remaining natural results.

This can also be called a type of Native Advertising because ads are planned to blend into the user interface and sometimes the user does not distinguish between the natural content and the advertising of a service.

Here you see the first 4 results and the last 3 results are paid results, which means a total of up to 7 ad results would show up in the first page for a search term. So if that keyword has more than 7 paid results, how does your company want to appear on it?

Google has created a bidding mechanism to advertise your company on this (the search page). However, the auction here is not simply that if you pay higher then you are likely to appear on it. It depends on an index which Google calls the Ad Rank index.

The Ad Rank index includes the following elements:

  • Bid: The amount you use to bid
  • Quality Score: The quality of your ads
  • Format: Factors related to formatting, other elements of the ad

Here is an example to make you understand it better:



Quality Format Ad Rank

Ad Position

1 2000 đ 9/10 High 18 1 (top)
2 3000 đ 7/10 Medium 15 2 (top)
3 4000 đ 5/10 Low 8 1 (other)

We have 3 advertisers with 3 different auction levels with different quality scoring levels, their formats also have different levels of interactive scores. Although the first advertiser has the lowest auction price, but their Quality is 9/10 and the interaction score on the Ranking is High, which lead to gaining a Ad Rank score of 18 points. The second advertiser gets 15 points and the third advertiser gets 8 points. We see that an advertiser with a higher Ad Rank will have a higher advertising rank. Like the above example, the first advertiser will appear in the top position of the TOP results, the second advertiser will appear in the second position of the TOP results, the third advertiser does not reach the Average Ad Rank score then their ad will land in the Other results below.

The ads in the Other section have some weaknesses. The ads at the top of the results will display the extensions such as sitelink, mobile, rate, etc. The ads under the Other section will not show the extensions.

We find that having the highest bidding money is not always the best solution. The key factor is the Quality factor of the ad. So how is this Quality Score calculated?

Quality Score is calculated based on the following factors:

  • Expected CTR (Click Through Rate)
  • AD Relevance
  • Landing Page Experience

Specifically, the first index Expected CTR (Click Through Rate) in an ad reflects for an exact number of people who see the ad, how many percent of them will click on the ad to visit the Landing Page. This is important because it shows Google that if an ad is not clicked by many people, it may has a problem. The point here may be that the writing style is not interesting, the keyword used in the ad is not very relevant to what the user is actually looking for.

And we also see that this is related to the Ad Relevance index, Ad Relevance means that an advertising on SEM only shows when people search for a certain keyword. Of course, the contents of that ad and the content of the landing page (the page where we lead the user to from advertising traffic) should also contain the keyword what the user is searching for. These two sections (ad content and Landing Page content) must be linked by containing keywords related to the search content. For example, you can not run an ad that sells jeans but pushes people to a landing page that sells khaki pants, because it’s irrelevant, and it’s not the product the user is looking for.

If the content of the running ad contains the keyword associated with the keywords in an Ad Group which is also running the ad as well as related to keywords in the landing page, the Ad Rank index will be higher. Since the more relevant, the  higher the Expected CTR is. As users find the relevance “well, this is related to what I am looking for”, the more users will click which lead to the increase in the expected CTR.

And the third indicator – Landing Page Experience is about when the user click on the ad content and visit the landing page: How long will they stay on the site (Time On Site)? Does the website contain keywords that are identical or close to the keyword they are looking for (Keyword)? How are the users’ conversions on that website? How do they interact with the website? Do they buy? Do they have any engagement or interaction? If the bounce rate is too high or the time on site is too low, it is also a relevant part. Or after accessing the website, they click the Back button to go back to the search page to select another result (the phenomenon I mentioned in the vlog bounce vs pogostick) which is the pogostick index. This is a very clear indication to Google that this content really does not fit. If the Landing Page Experience is good, the Time On Site is high, the Bounce Rate is low, customers make many conversions, there are many engagements on it, this proves to Google that this is the correct advertisement and what the user is looking for.

In conclusion, High CTR, with a good Ad Relevance (keywords that link closely to the content of the landing page and the content of the keyword in the Ad group) and a nice Landing Page Experience of the user(good user experience on a good landing page) will help Google realize that your ad has very good content, which helps increasing the Quality Score.

And the increased Quality Score will be the opposite and is inversely proportional to the Bid price. If you have a high Quality Score, you do not necessarily have to pay a high click-through cost for each ad, as compared to your competitor’s ad. In contrast, if your competitors have low Quality Score then they will have to pay more for each ad click to compete with you.

Here are the factors that determine the Bid Price – Bid, Quality Score, Format are the factors that affect the rankings of the search. I hope this Vlog help you understand what is SEM and the factors that affect SEM.

If you have any questions or need clarifications on these indicators, please ask in the comments section below of this video.

Thank you.

Facebook Comments


Hien are is Director of Marketing Store Vietnam Ringier AG. Digital Marketing and passionate about sharing knowledge as expected những scraped past tense as multiple users of coal, I was quyết create conversion.vn blog. If need to contact me, please email as through [email protected]

Leave a Reply

Your email address will not be published. Required fields are marked *

Name *
Email *