customer service vs treatment

customer service

noun
  • The act of providing services to customers before, during and after a purchase. 

  • A department that provides services to existing customers. 

treatment

noun
  • The process or manner of treating someone or something. 

  • Medical care for an illness or injury. 

  • A brief, third-person, present-tense summary of a proposed film. 

  • A treatise; a formal written description or characterization of a subject. 

  • The use of a substance or process to preserve or give particular properties to something. 

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