kiasi vs scared stiff

kiasi

adj
  • Unwilling to take a chance for fear that something bad or unfavourable will happen; cowardly. 

noun
  • A kiasi person. 

scared stiff

adj
  • scared to the point of being unable to move, or (figuratively) very scared. 

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