If you have the words to a song or even a partial phrase in your head, you can use a song lyrics search to find songs that contain that phrase. Follow these steps to find the title of that tune you keep hearing.
Follow the link to SongLyrics Advanced Search (see Reference). You will see a search box for an artist, album or song title. Use the second search box to find the title by the lyrics.
Enter the phrase into the search box -- for instance, enter "Shes real fine my" -- and click "Go." The search brings up the first 50 results.
Scan each title. For the search phrase above, the title is "409" by the Beach Boys. Click on the song title to see the full lyrics where that exact phrase would appear. Click on each artist and song title to see all of the lyrics to find the right one.
Try some different phrases to see which one brings you the correct results.