The searches that appear in the list only apply to searches that pass the rules for message validity and expiration. Additionally, the searches are 'canonicalized' before they are displayed. This means that all non alphanumeric characters are removed, and runs of white space are replaced with a single space. The entire string is then converted to lower case. These are the rules that most Gnutella based programs use when determining whether or not a shared file matches a search.
Most clients return a hit on a file if any one of the search keywords match the file.
BearShare only returns files if all of the keywords in the search string match a portion of the file name. This area displays the rate at which your files are being returned to other users as search results, and the portion of your bandwidth that is being used only for returning search results. This bandwidth is not in addition to, but rather, part of the bandwidth displayed in the Hosts Page. If you are sharing a large number of files and you place a big limit, or no limit, on the number of files returned in search results to other users searches, expect a large amount of bandwidth to be consumed rather quickly, as most Gnutella searches consist of file extensions only. To counteract this problem, while allowing large limits on returned search results, you can change the minimum number of characters considered in searches to 4 or higher in the Setup.