clear one's throat vs insufflate

clear one's throat

verb
  • Forcibly, sometimes mutedly, expelling air from one's lungs, sometimes to clear mucus, sometimes to attract attention to something; less vigorous than coughing. 

insufflate

verb
  • To breathe or blow into or on. 

  • To exhale upon baptismal water, or the one being baptised, as a ritual act. 

  • To inhale (a powder etc.). 

  • To treat by blowing a gas, vapor, or powder into a body cavity. 

How often have the words clear one's throat and insufflate occurred in a corpus of books? (source: Google Ngram Viewer )