memorize vs soak up

memorize

verb
  • To fully learn so as to have entirely available to the memory; to learn by heart, commit to memory. 

soak up

verb
  • To learn, especially passively or eagerly; to allow an experience to affect oneself 

  • To absorb or deflect a series of actions; to endure a behavior from someone. 

  • To enjoy some effects. 

  • To absorb or draw in a substance, especially all of that substance 

How often have the words memorize and soak up occurred in a corpus of books? (source: Google Ngram Viewer )