Peachyforum's native search facility isn't much help if you're trying to find a thread for e.g. Vika K. Google does a much better job, the only limitation being that they will always be a bit behind, i.e. they won't find very recent threads.
To use google as your peachyforum search tool, go into advanced search, enter Vika K in "this exact phrase" and enter peachyforum.com in "search within a site". Just so happens, this particular search would not have produced any results because there wasn't a thread for Vika K.