How to limit the "depth" of a folder-tree a filter returns in HP ALM?

I am trying to build some simple graphs in HP ALM to follow the advancement of test case statuses. We have a classic tree structure of test cases sorted in folders like

Root
-Level 1
--Level 2
---Level 3
---Level 3
---Level 3
--Level 2
---Level 3
-Level 1
--Level 2
---Level 3
----Level 4

etc

I figured the best way to get a filter that counts the test cases and groups them by their "status" is to filter by "Subject". I point each graph's filter to Level 1 and tt works, but the filter actually provides a column for every level of the tree. What i want it to do is to only generate columns for Level 2 and combine all the remaining sub-levels into a single result.

Is there a way to force such a thing?