갈피를 못 잡아요 · 갈피를 잡았어요 · 갈피를 잡을 수 없다
to get one's bearings; to make sense of something (mostly in negatives)
Example
설명이 너무 복잡해서 갈피를 못 잡겠어요.
The explanation is so complicated I can't make heads or tails of it.
Word parts
갈피 = the space between pages, as in 책갈피 'bookmark.'
Good to know
Almost always negative: 갈피를 못 잡다 / 갈피를 잡을 수 없다.