Returning relationships.tasks.data from entity/sequences/_search query

I’m trying to return a list of specific fields from sequences by using …/entity/sequences/_search. I’m specifying fields using the POST basic conditions - top level fields are no problem, but I’d like to also return the linked tasks from the relationships.tasks.data path - can’t figure out how to do it at all!

Obviously I could return ALL the fields including attributes and relationships etc. and filter out the ones I want, but that seems inefficient, I’d rather specify them.