I am trying to get better at notating songs, I am using Guitar Pro 5.
I try to notate small part of songs or riffs to learn it and getter better with it, so that I can write and notate own pieces there. But I definitely have a problem with unevem rhythms. (I don't know if theres a special name for it) For example bluesy rhythms or as a concrete example this song I gave up on yesterday (

) This example sounds easy at first, but for me it turned out a bit tricky.
I hope you understand what I mean with "odd/ uneven rhythms". 
I found myself wildly trying some punctuated notes and just guessed the right notes. (Rhythm is the problem, not the actual height of the tone)
Do you have some tips for me how to approach that? Are there special approaches, techniques or best practices, or is it all just a matter of experience?

Thanks in advance