How long are you waiting to see if you get ads matching your content ? A couple of refreshes or a couple of days. On my travel site I always try Yahoo ads first but 90% of the time ads are not relevant and I end up putting Google which 90% of the time is right on. Sample: A page on Santa Barbara California with pictures and content about visiting this central coast town and the Yahoo ads are about mold removal and re piping your house. Not only do they look out of place on the page no one will every click on them. After 24 hours I put Google ads same page and instant content matching. Is it taking longer than a day for the ads to match ? Maybe I should make a site about mold removal to get ads related to California Central coast
have you tried to put several targetting keywords near the ads ? or perhaps the lack of content makes yahoo ads a little bit confused in displaying which ads