How to filter cards using multiple conditions?

Here are many folders or documents in hierarchy or levels in my knowledge base. In each document, some of the rems are taged and/or marked with an icon.

Here is my question: How to filter the cards (or rems) that meet both of the reuquirements :

  1. the filtered cards with both an icon “%%tirangle_flag (to be simple, a flag)” and (Note: “and” here means an intersection not union) a tag “#hard”.
  2. the cards are in a certain document (not the whole folder)

By the way, I have tried to use Filter annoted in the sceenshot below, but the result is not what I want. To be indetails,

  1. it filters the cards with a flag or tag “#hard” (Note: the multiple inputs are treated to be an union not an intersection.). That is not what I want.
  2. After a filtered portal is created, when I Pactice the rems, all the cards (here means not only the filtered ones) in the certain will be in the quene. That also is not what I want.

Anyone can help?

Here’s a workaround until queries are implemented. Basically, you add a search portal to a rem, type the first keyword, and then filter that rem for the second keyword. Then add the filter as a new search portal by pressing plus and turn that new portal into a queue by using the three dots menu in the upper left.

Thanks a lot.
I just tried as you suggested. This trick works.

And your advice is for requirement 1 mentioned, I think.
The filter seems to find or search in the whole base.
Since there are many folders or documents or rems in a knowledge base, how to force the filter to do the searching job within a certain or constrained document? (to be a little clear, maybe it could be called “source-constrained filter”.)

Try manually typing in isDescendant: name_of_the_document. There’s an example using the daily doc in the same thread.