feel out vs go into

feel out

verb
  • To try to ascertain a person's point of view, or the nature of a situation, by cautious and subtle means. 

go into

verb
  • To get involved in; to investigate or explore. 

  • To divide, to be a factor of. 

  • To attack; to assault physically. 

  • Used other than figuratively or idiomatically: see go, into. 

How often have the words feel out and go into occurred in a corpus of books? (source: Google Ngram Viewer )