Seems like a problem to me too.
The official documentation at docs.tryton.org, while technically accurate, is too technical for people not familiar with tryton.
There is Howto - Tryton Discussion where anyone may write a Howto, but very few do, and usually the documentation is rejected as not being the right quality.
You may find out how a module is supposed to be used by checking the tests directory inside the module directory. By looking at how the tests scenarios are written one can usually understand how the module is intended to be used.
But this is technical too, so I guess Tryton is a technical product.
There are some efforts:
What do you think should be improved using the existing documentation infrastructure?