I' ve had success calling fall birds by simple KeeKee' s and Clucks.......or a KEEKEE-Run call. This without even breaking them up. They just naturally investigate a lost sounding bird many times.

If that doesn' t work and you have a visual on the birds, lay your bow down and try to catch one!! Scatter them as much as possible, in several different directions. Then get your gear and settle in close to where you broke them up. After a while you should start to hear them calling to one another trying to get back together........The same KEEKEE and KEEKEE-Run calls should do the trick.
Don' t draw until the birds head is behind something.