Just as with the 2CH coaxial toy RC helicopter, these toy versions use two counter rotating main rotors and by altering the speed of the rotors to one another, you can turn (yaw) the helicopter left and right (1st channel) as well as control lift (2nd channel).
The 3rd channel of control is used to control the speed and direction of a small tail rotor, but this tail rotor is mounted horizontally, not vertically like on most helicopters. It’s normally called the “tail fan” in this configuration.
The way it works is if it blows air down, the tail of the toy helicopter will pitch up slightly and the heli will drift forward slowly. If the tail fan direction is reversed and blows up, the tail will pitch down and the heli will slowly drift backwards.
It’s slow and sluggish at best, but better than shifting the center of gravity as it gives some forward backward movement control.