curious vs questioning

curious

adj
  • Tending to ask questions, or to want to explore or investigate; inquisitive; (with a negative connotation) nosy, prying. 

  • Containing or pertaining to trivalent curium. 

  • Leading one to ask questions about; somewhat odd, out of the ordinary, or unusual. 

  • Caused by curiosity. 

questioning

adj
  • Characterized by questions, inquisitiveness, doubt, or wonder. 

  • Unsure of one's sexual orientation and/or gender identity. 

noun
  • Interrogation. 

  • The action of asking questions; a survey; an inquiry. 

  • The act of challenging, wondering, and doubting. 

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