care vs concern

care

verb
  • To be concerned (about), to have an interest (in); to feel concern (about). 

  • To mind; to object. 

  • To want, to desire; to like; to be inclined towards. 

  • (with for) To look after or look out for. 

  • For it to matter to, or make any difference to. 

noun
  • Maintenance, upkeep. 

  • Worry. 

  • The treatment of those in need (especially as a profession). 

  • The state of being cared for by others. 

  • Close attention; concern; responsibility. 

  • The object of watchful attention or anxiety. 

concern

verb
  • To engage by feeling or sentiment; to interest. 

  • To relate or belong to; to have reference to or connection with; to affect the interest of; to be of importance to. 

  • To make somebody worried. 

noun
  • The placement of interest or worry on a subject. 

  • The expression of solicitude, anxiety, or compassion toward a thing or person. 

  • That which affects one’s welfare or happiness. A matter of interest to someone. 

  • A worry; a sense that something may be wrong; an identification of a possible problem. 

  • A business, firm or enterprise; a company. 

  • Any set of information that affects the code of a computer program. 

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