expound vs reveal

expound

verb
  • To set out the meaning of; to explain or discuss at length 

  • To make a statement, especially at length. 

reveal

verb
  • To communicate that which could not be known or discovered without divine or supernatural instruction. 

  • To uncover; to show and display that which was hidden. 

noun
  • The outer side of a window or door frame. 

  • A revelation; an uncovering of what was hidden in the scene or story. 

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