ambivalent vs shilly-shallying

ambivalent

adj
  • Alternately having one opinion or feeling, and then the opposite. 

  • Simultaneously experiencing or expressing opposing or contradictory feelings, beliefs, or motivations. 

shilly-shallying

noun
  • The action of the verb 

How often have the words ambivalent and shilly-shallying occurred in a corpus of books? (source: Google Ngram Viewer )