What are CH switches on controller for?

Hi,
Have a Lanyu 4 CH radio controller and a TW-748 electric plane with
throttle, aileron, rudder and elevator. The controller has the
following switches:
CH1 Rolling,yawing
CH2 Pitching
CH3 Motor power
CH4 Yawing,rolling
CH5 FPR, DLT

The really badly translated English user manual doesn't tell me if and
how the switches are to be used with this plane. Have tried a few
combinations, but can't see how the result could be useful.
Could anyone please elaborate me a little?

.