You don't even tell us what happens when you try to download...I'll just have a guess.

If files don't move into the download pane, try this
License (click)

If files get stuck connecting & then need more sources forever, they're probably fakes. Check out this thread for info & tips.
Fake files showing up in search results

Use the All Types search, look for artist or album rather than song title. Stay away from files with huge numbers of sources