Just to be sure BravoV .The kelvin clip 4 wire meter measures the voltage add and the current across the resistor and the unit calculates the value. Would that be a correct in the simplest terms ?
Basically at the 4 wires, 2 wires "force" a known constant current into the DUT, then the other 2 wires are basically a volt meter measure the voltage drop across it.
And then using the basic formula -> Resistance = Voltage / Current , to get the final resistance result.
So at most 4W DMM, you will see the terminals sometimes labelled "force" and "sense" , the "force" terminals mean the ones that force a constant current thru the DUT, and then the "sense" terminals are basically a voltmeter measuring the voltage drop.
As a hobbyist, in the past started in similar situation as op, with a limitation using single cheap DMM, without using the fancy 4 wires measurement tools, I made my self an adjustable constant current source power supply with 100ma and 1A capability just to use it for measuring low resistance, such as low ohm resistors, or sometimes measuring a cable like ordinary power cable which I suspected whether it was made from cheap fake copper inside.
PS : Just posted after Tooki, his post explains it better.