A few people have said the same thing, lately. Some days, I see very few results. I don't know if it's to do with the latest LW version(s) or some other issue. Some people have also seen a reduction in search results when using versions other than 4.18.8. And even with other Gnutella clients.

Have you tried disconnecting the Ultrapeers that you're connected to (click on the Monitor tab > highlight ultrapeers > remove)? Other UPs will automatically replace the ones that you've removed. New UPs can make a difference to the results that you see.

You can mark all those little .zip files as junk - over time, your junk filter will learn to junk them by itself. It's not perfect, but it can save you some grief. This thread is old, but has some good info about using the filter: Junk Filter

There's a hostiles list that you can add. This might also reduce the amount of crap that you see: The TechNutopia Fullsize Hostiles List for BearShare and LimeWire

Have you tried varying your search terms & using the 'All Types' rather than a more specific search?

Which version of LW were you using before you updated? Have you tried reverting back to that version, to see if it resolves the search issue?

If you think there's a bug in the latest LW, you can post at this other forum: LimeWire Forums
The developers don't post here any more, but maybe they'll help you over there?