fact-finding vs sifting

fact-finding

noun
  • The determination of factual information. 

adj
  • Designed to determine factual information; investigative. 

sifting

noun
  • The act by which something is sifted. 

  • The material which falls through a sieve. 

How often have the words fact-finding and sifting occurred in a corpus of books? (source: Google Ngram Viewer )