If, and that is a big if, I am understanding you correctly:
You require three clamp type probes, a single differential high voltage probe, and a 4 channel scope.
Connect the high voltage probe to channel 1 and set the trigger to that channel.
Clamp the current probes to each phase and feed them to channels 2,3 and 4.
Make sure that all of the clamps are oriented correctly; i.e. that the arrow faces the motor.