Hello, It has been a few weeks since I see my header ad unit changes from a 90% relevant ads to 5% relevant ads. Generally, my blog is about humour, but the header ad unit aren't showing anything related. Sometimes, it shows spyware stuff, sometimes volunteer stuff, and sometimes even army or disaster related keyword. I'm running a WordPress blog, and I don't know how exactly I should use those AdSense focus tags. When I'm viewing a certain post on my blog, it's quite relevant to the topic. It is weird as it's working so perfectly before this but it changes all in a sudden. Any idea or comment? Thanks.
Try using section targeting: https://www.google.com/adsense/support/bin/answer.py?answer=23168&topic=8441