Dear Junior Members (especially those that get porn in their search results)
As LOTR says, you can do various things to filter out porn from your search results but you have to understand that, apart from your good selves, no one can stop this from happening.
The Gnutella P2P network has no central authority and no central server, it entirely consists of thousands of individually owned PCs and that you are at the mercy of whatever files an individual wants to share, no matter how strange. That also means that if you download offensive material by mistake there is no one to complain to, no switch or filter that can be turned on to keep this stuff out.
To learn more about the workings of P2P networks go to this web page:
http://computer.howstuffworks.com/file-sharing2.htm
Therefore, if you get a mislabelled file, pornography or any other objectionable material in your search results then reset your filters (both IP an file extensions) and try again, with practice you will get more of what you want and less rubbish.
UK Bob