expound vs nutshell

expound

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

  • To make a statement, especially at length. 

nutshell

verb
  • To summarize (from the term in a nutshell). 

noun
  • A short book summarizing an area of law. 

  • The shell that surrounds the kernel of a nut. 

  • A small boat; a boat considered small in comparison to the seas. 

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