I don't think it searches every comp. on the network as this would slow it down for everyone.
You could consider going with the Pro version which will connect you to more hosts and should get better results. If you do get it here and not from a scam site:
LimeWire PRO
Some other threads to check out:
Skills to continue downlds, Downld speeds, Searching, optimal performance Maximizing upload/download Success with LimeWire