In the new copy design the drawings cannot be shown together with the models tree. They are separated above. Provide another view option to show the related documentation below the models as it was in copy design 2014.
If a model has two or more drawings, the user can already identify this when selecting the model for copy. Otherwise the user must find the related drawing in the drawings view which can take a long time if drawings and models not have the same file name or many drawings marked for copy.