This thread:
https://forum.arduino.cc/t/pro-micro-power-3-3-or-5-and-whats-this-j1/507848
has a schematic of the original Sparkfun Pro Micro. If yours is the same circuit, the RAW pin should be one diode drop below your USB supply voltage. If you get zero volts there, then your Pro Micro clone must have a different circuit.
Edit: If you also get zero volts on Vcc, and the Pro Micro still runs, then something is probably wrong with your meter.