I have a tablet with Android 5.0.1.
I am the main User.
I have set up a Restricted User account (Settings > Users).
When I log into this account and open, for example, Google Play Books, it's showing all the books associated with the main User's Google ID.
This is a security issue.
I want the second account to be able to a separate Google ID associated with it.
From within this Restricted account, when I go to Settings > Accounts, I see no way to add a second Google ID specifically for this second user.