Is this a gnutella network file or a torrent file?
If a gnutella network file it might be a fake file. There are several around that draw people in but never actually downloads.

However, there's also a chance that all those people with the file are legitimate users but all their upload slots are busy. In that scenario I'd use re-search for the file then 5-10 mins later use the Get More Results option to try to find more people with same file.