Btw, are there any other web pages / tutorials / books / chapters that make us understand Threads in Perl in a better way? PerlDoc has very few examples and it's difficult to understand some concepts ... I'm really not very happy with the perldoc help pages.

I'm personally unaware of other available documentation. That doesn't necessarily mean that they don't exist.

At times I get confused about the documentation for a new function/module that I'm trying to use. What I usually do is very similar to BrowserUk's suggestion. Just write some small test code to test out the function/module to see if I understand what it is doing and how I'm supposed to use it. Sometimes I personally find that kind of experimentation to be far more useful to me in the learning process than the documentation.

In fact, even if I think I completely understand the documentation, I'll still do some small experimental code just to verify if I got it right or not. As BrowserUk suggested, it's much easier to debug that small experimental code while trying to learn the new stuff. And once you have figured things out with the small experimentation code, then you're ready to implement it in the real code that you're trying to develop.