I had ordered/downloaded a few songs that are no longer visible - what am I doing wrong?

Hello MPGadois, 

Thanks for reaching out on the Apple Support Communities. We understand that you're not able to see some songs which were in your Library. 

If you're an Apple Music or iTunes Match user and this occurred after you turned on the Sync Library, follow the steps in this article: If songs are missing from your music library after you turn on Sync Library. 

If you see that songs are grayed out, follow these steps: If your songs are grayed out.

All the best.