When the user permission Quick Search Invalid or Returned Leads is enabled, users are allowed to specify if they want to search for leads that are Valid, Invalid, Returned, or search against All Leads.
Note: If a user doesn't have the permission Quick Search Invalid or Returned Leads enabled, they are defaulted to only searching valid leads.
If a lead is Returned or Invalid, the Quick Search window displays a flag to aid users in identifying the lead.