Depending on the id3tags users put on their files, sometimes these fields appear empty. I use version 2.3, and I know that 1.1 seems to work also, 2.2 does not seem to work correctly and a lot of users use that. It is also the default for iTunes which is a pain, but it is easy to convert your entire iTunes library in a fairly short time. (which does not help you I know!)
Am I right in thinking you are getting a list of results in name column the main search page, but nothing in the Artist/album/title page. If so this is, as I have said, due to the way sharers are tagging their files and there is nothing that LW can do about it.
I hope this answers your question, otherwise, we'll have to try again
