Try filtering out the following file extensions for a much better search result. .wma, .exe, .rar, .html, .com, .zip, .mov. Go to Tools > Options > Filters > Keywords. After you put the extensions in to block, hit apply and then OK. This will clean up a ton of crap. Also see link below
This thread is long but it has some helpful info.
Junk Filter
Hope this helps..
