discreet vs having all one’s marbles

discreet

adj
  • Respectful of privacy or secrecy; exercising caution in order to avoid causing embarrassment; quiet; diplomatic. 

  • Not drawing attention, anger or challenge; inconspicuous. 

having all one’s marbles

How often have the words discreet and having all one’s marbles occurred in a corpus of books? (source: Google Ngram Viewer )