I always MAAAAA them if they are moving quickly with purpose - usually with just my mouth - If you wait for them to stop in this case - they are out of range and its too late.

If they are out of range - I' ll try a grunt call to get them to " swing by" a little closer.

In both cases - I utter a quick - less than one second - Grunt/bleat of sorts - so the deer cannot " fix on" my position.

If the deer is slowly moving through - picking along, maybe browsing - I' ll never make a peep.