It's a feature. lol only joking. Are these gnutella network files or torrent files?
Busy host means their upload slots are full. Waiting for resources means it cannot find the same hosts as last time online. So best thing to do is re-search the file as you did in the first place. Then use the Get More Results by right-clicking the search tab 10 mins or so later. The idea being to find more people who are sharing the 'exact' same file.