You can limit a group-selection to a single type of object by selecting the tool used to create that object instead of the Select Objects tool, then drawing a selection marquee around the objects.
For example, to group-select wall cabinets only, select Build> Cabinet> Wall Cabinet from the menu, then hold down the Shift key
and drag a selection marquee around an area in your plan. When you
complete the marquee, only wall cabinets will be selected.
This method works for all objects except for walls and wall openings such as doors, windows and fireplaces created in walls.