turbid vs unascertainable

turbid

adj
  • Unclear; confused; obscure. 

  • Having the lees or sediment disturbed; not clear. 

  • Smoky or misty. 

unascertainable

adj
  • That cannot be ascertained; uncertain, unable to be determined or discovered. 

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