under the carpet

(idiomatic, location) Such as to be hidden from plain view (and thus easily ignored or overlooked).

Example: Used other than as an idiom: see under,‎ carpet.
2005, Devi S. Nambudripad, Freedom from Environmental Sensitivities, page 35,
  When the carpet layers came in and removed the carpet she said there were millions of black eggs and tiny worms crawling under the carpet.
1989, Walter Joyce, Hillel Ticktin, Stephen White, Gorbachev and Gorbachevism, page 58,
  But in the 1970s the process went into reverse, as more and more 'bad' data went under the carpet.
1999 June 30, Kenya National Assembly Official Record (Hansard), page 1119,
  It seems as if it is happening and it is being washed under the carpet.
2006, Joint Committee on Human Rights, The UN Convention Against Torture (UNCAT): Nineteenth Report of Session 2005-06: Volume II: Oral And Written Evidence, page 27,
  The Bill is going to apply to a much wider group of people and I think it will sweep an awful lot of things under the carpet.
2009, B. Vithal Shetty, World as Seen Under the Lens of a Scientist, page 233,
  Worldwide nuclear proliferation committed by a single nation to create an Islamic nuclear bomb has been swept under the carpet by the United States.
2009, Christopher Johns, Becoming a Reflective Practitioner, page 139,
  Conflict is brushed under the carpet.