Query Creating With Form Entry

I need to create a form, in which would be a query at the bottom.

I have table f.e. "A" in which is all data about cars.
I have table "B" in which is all data about customers.

I would like to create form "B" - which would add new customers, but at the bottom of that form I would like to see tables "A" filtered results.

Something like: In form B I create new customer. When I insert what car they want and how much they can pay, at the bottom generates query which would show all possible results from table "A".

With one customer I know how to do it. But when I insert second customer in the form, that query stops working while it doesn't know from which entry it should take the information. I don't know how to tell, that the query should take the data from the customer ID1 when I'm looking customer ID1, and from customer IDX - when I'm looking customer IDX.

I thought, perhaps it possible to create button with macro - when I press the button it copies all data from the current entry, it pastes in the form where is only one entry and works with query, than generates the query results which will be showed in the same entry that I pressed the button.