sucking from the closest point of extraction from the tent/room is the most efficient way to do it... but it also is the easiest way for smells to seep in from your hoods' glass.
you can push from one side of the hoods, and pull from the other side closest to your extraction point from the house. this should cut back on smell outside a lot.
you can also tape all the glass seams on your hoods to help prevent air seepage. or you can get a better seal on the glass by buying some new/better weather foam stripping than what the companies put on them to begin with.