How to see in an table item, every other item refers to it using connected columns

I have one Board, containing all my field teams (subcontractors).
I have another board, with all projects, that we need to complete. These projects are completed by assigning them to subcontractors.

I have set up a connected column, into which we can insert the subcontractors.

Now, I would like a way, to see ALL the projects, that are assigned to a single subcontractor.