expound vs specify

expound

verb
  • To make a statement, especially at length. 

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

specify

verb
  • To state explicitly, or in detail, or as a condition. 

  • To bring about a specific result. 

  • To include in a specification. 

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