assured vs under wraps

assured

noun
  • An insured person. 

adj
  • Guaranteed; secure. 

  • Self-confident; self-assured; sure. 

under wraps

prep
  • In secrecy or in hiding. 

  • Of a horse: restrained from performing at its best in a race, so as to mislead others regarding its potential. 

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