/bʊk ʌv kəmˈpleɪnts/ – Phrase
Definition: sổ góp ý kiến, sổ khiếu nại.
A more thorough explanation: A “book of complaints” refers to a record or register maintained by an organization, business, or institution where individuals can formally document their grievances, criticisms, or concerns regarding the products, services, or conduct of the entity. This book is typically used for the purpose of tracking and addressing complaints in a systematic and organized manner.
Example: The customer filled out a form in the book of complaints to document their dissatisfaction with the service they received.