DLC
How to find a DLC?
There is no way to distinguish filter/check DLCs for accounts since they are listed the same as other purchases in transactions.
The only thing you can do is search for the game and look in the transactions.
For example, lets say Im looking for B03 Zombies edition, I search for B03 and then look in transactions across many accounts till I find what I need
(at the bottom of the account page)