Ok, I think I understand what you're looking for.
Well, according to NIBOGO in
this thread over at simplemachines.org, this is a built-in feature of smf2.0. I've been looking for that feature on my 2.0RC3 forum, however, and have not been able to find it.
There's the
Search Results Mod but it's only supposedly compatible up to version 1.1.5 of smf. However, if you look at the parser, it looks like the mod only edits the search template, so you may be able to install it or else do a manual edit without too much problem. I haven't looked into it all that much, but that's what I've observed thus far.
Hope that helps.