conceal vs contain

conceal

verb
  • To hide something from view or from public knowledge, to try to keep something secret. 

contain

verb
  • To put constraints upon; to restrain; to confine; to keep within bounds. 

  • To include as a part. 

  • To hold inside. 

  • To have as an element or subset. 

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