How do I see and share older iTunes purchases?

I am trying to share some music album purchases that I made on iTunes with family members via Family Sharing. However the only purchases visible are ones made within the past 1-2 years at most. Why can I not see these purchases, even when I can see it directly on my iPad for example? I have not changed Apple IDs... I even have some prerelease tracks from an album that I purchased that are not visible for sharing, even though the rest of the later released album is available and already shared.

I am terribly confused.