between a rock and a hard place vs in difficulty

between a rock and a hard place

prep
  • In a difficult and inescapable position. 

  • Having the choice between two unpleasant or distasteful options; in a predicament or quandary. 

in difficulty

prep
  • experiencing problems 

How often have the words between a rock and a hard place and in difficulty occurred in a corpus of books? (source: Google Ngram Viewer )