deliberate on vs reflect on

deliberate on

reflect on

verb
  • To think carefully about (something), and give it due consideration. 

  • To give an impression of (used with an adverb). 

  • To access details of (a data type, etc.) at run-time using reflection. 

How often have the words deliberate on and reflect on occurred in a corpus of books? (source: Google Ngram Viewer )