discontinue vs knock something on the head

discontinue

verb
  • To consciously cease the ingestion or administration of (a pharmaceutical drug). 

  • To interrupt the continuance of; to put an end to, especially as regards commercial productions; to stop producing, making, or supplying. 

knock something on the head

How often have the words discontinue and knock something on the head occurred in a corpus of books? (source: Google Ngram Viewer )