furtherance vs restraint

furtherance

noun
  • Promotion. 

  • Advancement or progress. 

  • The act of furthering or helping forward 

restraint

noun
  • something that restrains, ties, fastens or secures 

  • control or caution; reserve 

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