Expand query really simplifies one’s Flows, but the syntax is a killer. I forget this after 10 minutes so a super brief primer.
Below, expanding the query to get the licenses attached to a system.
The key is to ensure the lookup table uses the navigation property table name, easily seen in the all fields view. That capital letter is vital !
Select any required fields or leave out to get all. To go deeper just add an embedded expand in the same way:
To use these values requires more fun:
Get the body output from another field on that action, and add in the expanded entity and field required after body. This has to be done by the expression editor.