During the rut it’s natural for a buck to hear the sounds of more than one deer. After all it takes two to tango. I like to carry one grunt call and two different bleat calls with me while hunting. This gives the illusion of there being more than one receptive doe in the area. Giving least three bleats to every grunt has worked best for me. Remember does don’t estrous bleat to sound their receptiveness, they bleat when they are trying to flee an overly aggressive buck.
In the end the tool that takes most deer is patience.