Oscar,
Welcome tot he forum.
First caution, don't run the pump with little or no flow. With blocked flow all the motors work is going into heating the water in the pump chamber as you have felt. If it gets hot enough it could ruin the pump. As for the skimmer line blockages, I guess the first thing I would try is a wet/dry shop vac to try and suck the stuff back through the skimmer. Stick the vac hose onto the skimmer hole and see what you get out. If you have stuff really jammed then I think the only solution is to try a snake from the pump end back toward the skimmer. Never had to try this but be careful and don't get too aggressive and damage the pipe. People in the business probably do have ways to clear lines safely so that may be your best bet. They could also educate you more on your specific setup but as Mom said, if they try and sell you something really expensive, shoot it by us first.
Al