Wade through
Definition 1 of 2
Pro Tip 1/3Figurative Use
Used to describe mental or emotional efforts, not just physical ones. 
I need to wade through all the new rules to understand the game.
Pro Tip 2/3Overwhelming Tasks
Implies facing a large or complicated task that can be tiring. 
She's wading through all the applications to find the right candidate.
Pro Tip 3/3Time-Consuming
Suggests a task will take a lot of time to complete. 
He waded through the archives for hours looking for the record.