expressis verbis vs unequivocally

expressis verbis

adv
  • Expressly; explicitly. 

unequivocally

adv
  • In a way that leaves no doubt; in an unequivocal or unambiguous manner, unquestionably. 

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