Life taught me that what you know is just one, very little thing.
The rest is not knowledge of a subject that you're going to perform but knowlegde of sb who could recommend you as a person to work.
It's a very sad reality but we must accept the life and try to survive somehow.
Let me apologise you for not writing Polish but I can hardly produce any utterances in this language as I'm hungarian working here.
But for my colleagues I wouldn't have my current position.