clasp vs hold onto

clasp

verb
  • To take hold of; to grasp. 

  • To shut or fasten together with, or as if with, a clasp. 

noun
  • A fastener or holder, particularly one that clasps. 

  • An embrace, a grasp, or handshake. 

hold onto

verb
  • Used other than figuratively or idiomatically: see hold, onto. 

  • To manage to keep something. 

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