dog sleep vs drowse

dog sleep

noun
  • A shallow sleep; a pretended sleep. 

drowse

noun
  • The state of being sleepy and inactive. 

verb
  • To nod off; to fall asleep. 

  • To be sleepy and inactive. 

  • To advance drowsily. (Used especially in the phrase "drowse one's way" ⇒ sleepily make one's way.) 

  • To make heavy with sleepiness or imperfect sleep; to make dull or stupid. 

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