Broodmother, Warlock, Lone Druid, Nature's Prophet, Chen can summon units, and it's a challenge to control them properly.
You can improve your efficiency adjusting settings in DOTA 2.
1. Assign a button to choose hero.
2. Assign a hotkey to select all other units.
3. Assign a hotkey to select all units.
In Options -> Game enable Unified unit orders.
From now on you'll be able to control all units with the help of CTRL.