Web Pages Not Found on Yahoo Site Explorer

I have a fairly aged site (registered dec 2010) and not completely being found on Yahoo's site explorer. I have over 90 posts with 20 pages of content and Yahoo site explorer only shows 3 pages from my domain. What do you think the problem is? I tried many SEO plugins and afraid I may have set some setting so that spiders won't crawl my pages. Or is it my url naming? Right now I have it set to http://www<domain>/<postname>

Url naming should not matter. Do the pages show in Google's index? If so I'd forget about Y! explorer.