expose vs open up

expose

verb
  • To reveal, uncover, make visible, bring to light, introduce (to). 

  • To submit to an active (mostly dangerous) substance like an allergen, ozone, nicotine, solvent, or to any other stress, in order to test the reaction, resistance, etc. 

  • To make available to other parts of a program, or to other programs. 

  • To abandon, especially an unwanted baby in the wilderness. 

  • To subject photographic film to light thereby recording an image. 

open up

verb
  • To reveal oneself; to share personal information about oneself; to become communicative. 

  • Synonym of cheat out (“to face or turn toward the audience more than would be natural”) 

  • To begin running, driving, travelling, etc., at maximum speed. 

  • To commence firing weapons. 

  • To rain. 

  • To open. 

  • To widen. 

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