on thin ice vs unsettled

on thin ice

adv
  • dangerously, hazardously, delicately 

prep
  • In a dangerous, hazardous, or delicate situation; at risk. 

unsettled

adj
  • Unpaid. 

  • Not populated, having no settlers or other inhabitants. 

  • Disturbed, upset. 

  • Not in a steady condition, uncertain, subject to change. 

How often have the words on thin ice and unsettled occurred in a corpus of books? (source: Google Ngram Viewer )