unclear vs unsearchable

unclear

adj
  • Not easy to see or read; indecipherable or unreadable. 

  • Ambiguous; liable to more than one interpretation. 

  • Not having a clear idea; uncertain. 

  • Not clearly or explicitly defined. 

verb
  • To undo the process of clearing. 

unsearchable

adj
  • That cannot be investigated or searched into; unknowable, inscrutable. 

  • Not capable of being searched; on which one cannot perform a search. 

  • That cannot be sought out or looked for. 

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