how's that vs say what

how's that

phrase
  • Used to ask someone to repeat something 

  • Used to make an appeal to the umpire as to whether the batsman is out or not 

  • Used other than figuratively or idiomatically: see how, is, that. 

say what

phrase
  • What did you say?; Huh?; expresses incredulity. 

How often have the words how's that and say what occurred in a corpus of books? (source: Google Ngram Viewer )