convolute vs open can of worms

convolute

verb
  • To confuse, mix up (something) with something else. 

  • To make unnecessarily complex. 

  • To fold or coil into numerous overlapping layers. 

adj
  • Convoluted. 

  • Coiled such that one edge is inside, and one outside the coil, giving a spiral effect in cross section. 

open can of worms

How often have the words convolute and open can of worms occurred in a corpus of books? (source: Google Ngram Viewer )