Hi ,
From your description, I believe that your usual workflow involves importing a model using the Collapse by Material collapse option, which groups all imported meshes with the same material is a single object in the Scene Graph on the right, with the object being named after the material.
From your screenshot, it looks like you might have imported using the Keep Hierarchy collapse option, which imports the model using the same model hierarchy as the original design program, so all objects are imported exactly as they were, with the same names and ungrouped.
If you re-import using the Collapse by Material option, it should allow you to view the all elements sharing that same material.
Best,
Raghib