Complicate tree, (Umm... the opposite of simplify?)

I am not sure if i quite understand the way branches work (but i think i could if someone helped :)). I am having some trouble matching the branches sometimes, and i dont know how to approach this problem.

I noticed that, for example, reversing the list twice, would add two 0:0 in the brackets, and sometimes i can match the branches that way. What i find confusing is when i get branches that have a number somewhere in between, but stilll a bunch of zeroes behind (meaning no sub branches?).

How do you do this matching?