text: from django.utils.translation import ugettext_lazy as _
  
  from mayan.apps.documents.search import (
      document_file_search, document_file_page_search, document_search
  )
  
  # Document file
  
  document_file_search.add_model_field(
      field='file_pages__content__content', label=_('Content')
  )
  
  # Document file page
  
  document_file_page_search.add_model_field(
      field='content__content', label=_('Document file content')
  )
  
  # Document
  
  document_search.add_model_field(
      field='files__file_pages__content__content',
      label=_('Document file content')
  )
  