Study subset of REMs in a document

I’ve got a top level document formatted like this
topic
REM
REM
REM
topic 2
REM
REM
… and so forth. I am trying to study the REM in a subset of this document. I indent, them, I move them, I create new folders…no matter what I do all the REM in this document show up in the flashcard trainer.
Let’s say I move topic 1 into it’s own folder and choose the document queue in the upper right for flashcards. The resulting set of flash cards will show me all the topics in the original document. I’ve tried everything I can think of to just study a subset of these cards only.
What I can do is study the REM only in a single topic, like topic 1. That works. What I can’t do is study topic 1, topic 2, and topic 3, ignoring 4, 5, 6…The flashcard system seems determined to show me all in this list no matter where I place them.

You may portal those rem into a separate document and practise that document’s queue.

Also check the documentation and the video demonstration on Creating Custom Queues (For Power Users)

I’ve tried both these and can’t seem to get them to work.

I’ve tried moving a subset of REM into different folders, different hierarchies, also tried creating a portal for just the REM I wish to study. Also tried filtering REM by header/color.

The main goal would be to just study those REM I select without spaced repetition. It seems like the repetition algorithm will show me REM outside the document or it won’t let me study at all, saying I’ve already studied them.

If I have a topic/document with several REM, I can do a study queue for just that topic and it works. If I have a document with several topics, each with multiple REM, that’s where it breaks. In other words, it seems like I can queue a document with just REM and will get just those REM. I cannot queue a document with multiple docs within it, each containing REM to study.