For example,I tried PR for a few weeks and I gave up this because I wasted much time but I din't get the information.

One good thing from this PR system that helps me is skimming because after that I read and understand faster.

And I would like to ask too why there the people who understood the system doesn't create blog's or just doesn't share information in forums if they learnt such a wonderful thing?

In my country there is a company which teatches speed reading but they are cheaters(I read it in many forums),so it make really hard to believe that PR is true.