easen vs water down

easen

verb
  • To make at ease; make easy or easier; (by extension) to soothe; comfort; relieve 

water down

verb
  • To make less restrictive; to make more lenient. 

  • To simplify or oversimplify; to make easier; to make less difficult. 

  • To make weaker, less effective. 

  • To dilute; to add water to. 

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