concealment vs dissimulation

concealment

noun
  • The condition of being hidden or concealed. 

  • The practice of keeping secrets. 

  • protection from observation or surveillance. 

dissimulation

noun
  • Hiding one's feelings or intentions. 

  • The act of concealing the truth; hypocrisy or deception. 

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