In order to know what to claim, you must search the list for the musical works that you represent. This can best be achieved by searching by the track (song) title and/or artist.
While there are searchable fields for “Writer” and “Publisher/Rightsholder”, please note that the content of these fields is often empty, inaccurate or too generic to be useful (i.e. “pending account”, “suspense account”, “unknown” are variables often found in this field). As such, you cannot simply rely on those fields for searching purposes, and should focus on the artist name, album title or track title for works where you know you have a musical work for which you have not received royalties.