For a site that is always advertising for PHP devs, it amazes me that the search is so limited. I assume that you use some database backend for that and so why don't you have some logic and limited regular expression processing in your search? In fact it might be easy to buy some already existing search engine for your site that supports lots of logic.
For example I just looked at results that had the word "pierced", since one word searches seem to be the only thing allowed, or words are logically 'anded', which is losing,and got lots of false positives become some Ukranian codes a fixed set of keywords to his gallery that said 'piecings: none', hence false hits. In fact this user comprises most of the hits for that search. You need to search on the user name as well as any keywords and enable logic such as 'piercing not '
