help oneself vs speak for

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. 

speak for

verb
  • Used other than figuratively or idiomatically: see speak, for. 

  • To represent an intrinsic quality 

  • To claim, reserve, or occupy. 

  • To speak on somebody's behalf. 

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