I see a couple of problems.
Initially, try removing the bleeder valve(s) completely. Sometimes rust
blocks the bleeder. See if you get flow with the bleeder out. I
if not then lets continue. First, the RR bleeder. It should flow just like
the LR. Since the LR flows properly, the problem has to be between the hose
and the wheel cylinder. Check to make sure the brake line was not crimped
by a PO who had the car towed. The location of the line makes is
susceptible to being crushed by a tow trucks hook.
Now, lets track down the front problem. Did the master run dry? If it did,
you may have an air lock. Loosen one of the lines where it enters the
master. Protect the paint. Have someone press the brake pedal. Fluid
should come from the loose fitting. If not, treat the fitting as a bleeder,
and try bleeding it. If you can't get fluid out, you have a plugged master,
very rare. No do the other front line. Once you have fluid coming from the
master, go to a caliper. Fluid should come out. If not, try disconnecting
the hose from the caliper and see if fluid comes out. No? loosen the hose
where it joins the hard line and try it. You may have a bad hose which
prevents fluid from flowing. If you have fluid coming out of the master,
but not out of the line where it joins the hose, you have a blockage. Check
to see if there is any damage to the line. If not, try using compressed air
to clear the line.
Good luck, and don't drive in back of me until you get it fixed (VBG).