We have various custom child entities (for example, Account Profiles, or Customer Products). What if I want to pull list of All Accounts that have Profile A and Profile B (not just whether they have one of the other)? Or an Account that has Product A and B.

This is not possible in current construct of advanced find. I can only join in to the related Account Profile entity once from Account.

Why not make it possible in Advanced Find to join in multiple related records (currently disallowed) as an inner join - which means both criteria must match. This way, I could select from Account Profiles (Account), where Profile = A, and then select Account Profiles (Account) again where profile = B. The backend query generator build two inner joins to the Account Profiles table with the defined criteria.

Also, how does one pull list of everyone who has Profile A, but NOT profile B. This would require a NOT IN type join to the Account Profile where the profile equals Profile A. I will post new suggestion for that.