See, if it's in All Tracks, and you've got your tags filled out, then it probably also appears in Years, Artists, Albums, and Generes

Actually a song will be listed, as far as I can tell, in all soup views regardless of tag data. It will just be listed under the "none" branch of each view if that tag is missing. Which is great for finding tracks that are missing tag data (or have things like years set to "0" or other invalid values).

Bruno