I am an engineering grad student in Canada. I did my undergrad in the UK where I was exposed to typical topics that engineering majors learn - calculus, Fourier transform, linear algebra etc. I like to think that I have an intuitive understanding of some of the concepts I learned about.

However, when I'm reading a paper that relies on heavily on mathematics I have trouble following it. I don't understand how to breakdown complex expressions and "read" them. I am beginning to worry this is slowing me down and I may fall behind in my career and understanding of technical

It feels like a form of mental block. When I'm stuck, I'll google relevant material but basically end up in a rabbit hole. I am generally good at teaching myself things but I fail pretty hard at such papers.

Is there a resource that can teach me how to "read" complex expressions?