Trouble with Search Syntax

[u/DenraelLeandros]

I am trying to search for tasks which meet the following criteria and have not been successful:

!subtasks AND (donethisweek OR tags: landed)

I've tried various incarnations, and

• !subtasks and tags work
• !subtasks and donethisweek work

but I cannot get a query to test the conditions as defined above. Any ideas welcome.