seize upon vs suss out

seize upon

verb
  • To take up, embrace, enact, or turn eagerly to (a plan, idea, ideology, cause, practice, method, etc.); to grasp, understand, and accept quickly; to adopt wholeheartedly or vigorously. 

  • To grasp or take hold of (an object) suddenly, forcibly, or tightly. 

  • To take possession of or claim (an idea, person, event, etc.) as one's own; to assimilate, absorb, annex, co-opt. 

suss out

verb
  • To come to understand (a person). 

  • To manage to work (something) out, to determine (something). 

How often have the words seize upon and suss out occurred in a corpus of books? (source: Google Ngram Viewer )