you can suppress rows based on a next() or previous() funtion.
Or group on a field (like order#) and suppres the details completely.
What I think you are ultimeately aiming at here is to also get totals at group and report levels. SUpressing rows only hide them and do NOT exclude them from totals.
YOu will have to use Running Totals with unique evaluation options to get to that if that is also part of your design.