The easiest solution is to repeat each search several times as hosts are continuously appearing and disappearing.
Another answer is to use more than one client and different P2P networks. If you have a fast connection, you can even have them open simultaneously (although this is not a very efficient use of resources). On the Gnutella network I use Limewire and Shareaza and on the Fastrack network, I use Kazaa Lite (which often returns a larger number of hits for each search than Gnutella). All of these can be downloaded for free. Often, if a file does not appear in one, it will appear in another.
Apart from the ones I have mentioned, there are several other clients and networks that many people swear by. This forum is a good place to start if you want more information. Try these links:
http://www.gnutellaforums.com/showth...threadid=14583 http://www.gnutellaforums.com/showth...threadid=12658