Filtering the drawing to the items used or unused in the current schedule

Open the tab with filters first.

There, pay attention to the third section, which is "Schedule".

When you need to see in the drawing the elements used in the chosen schedule, tick the option "Scheduled".

When you need to filter the drawing to the elements NOT used in the chosen schedule, tick the option "Unscheduled".

Note!

The filter's results are based on the current active sheet in the schedule.