AdSense uses special crawler bot to examine what topic on a page is. If your page is talking about "tourism object", AdSense will deliver ads about "cheap travel accomodation, hotel and others related ads". Its called contextual ads.
AdSense also will consider "where the visitor come from". I'm in Indonesia, so most possible AdSense will deliver "cheap airline in Indonesia, cheap hotel in Indonesia, etc..". Its called targeted ads.
Try Google's webmastertools to examine your pages.
Example of significant keywords of this blog. |
Try AdSense ad section.
Example you write about a tourist destination in three paragraphs. First paragraph tell about place name, where its situated, panorama, etc.. Your second and third tell about your experience/opinion. And you think the first paragraph is most important content, you can try:
<!-- google_ad_section_start -->
//first pharagraph goes here
<!-- google_ad_section_end -->
Keep unrelated ads away.
You can try Allow & Block ads. Got to your AdSense dashboard, select Allow & Block ads, on Overview > Product dropdown, select Content.
Allow & Block ads option |
Ad Link Unit
I never get unrelated ad on my Link Unit, so you may try to put it on precious position, eg.: under title, inside article etc.
Be focus on your blog theme/topic
If your blog article theme is tourism, and no other kind theme, you will get more related ad. Most of successful AdSense publisher focus on their topic. You can check here, may they give you inspiration. I hope be listed there :).
Last mantra: Be patient :)
All your changes will take effect on next time crawler visit your page. So don't rush uh :).
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