Support for multi-layer project?

I have a common code project shared between multiple platform project, my iOS/Mac projects is submodule in a git, structure is like:

my-app
|_ common
-|_ xcproj
|_ ios
-|_ xcworkspace
-|_ xcproj
|_ mac

The problem is that the copilot cannot find the file in the common project even if the workspace included it, resulting in error/repeatitive searching file, how should I deal with this or a new feature is needed? Thanks!