come across vs help oneself

come across

verb
  • Used other than figuratively or idiomatically: see come, across. 

  • To find, usually by accident. 

  • To produce what was desired; come up with the goods. 

  • To give an appearance or impression; to project a certain image. 

  • To change sides; to cross over to work for the opposition. 

help oneself

verb
  • Used other than figuratively or idiomatically: see help. 

  • To serve oneself, especially to take food or other supplies, rather than wait to be served by another; used to indicate friendly permission or invitation. 

  • To exhibit self-control. 

  • To take something freely; to serve oneself without restraint. 

How often have the words come across and help oneself occurred in a corpus of books? (source: Google Ngram Viewer )