The Keyword... menu item displays a dialog box that
  includes the available keywords, which are subjects
  associated with certain topics. The application
  determines what the keyword names are and which
  keywords are associated with specific help topics.

  To see a list of help topics associated with a specific
  keyword, either select the keyword from the list or
  enter it in the Keyword entry box, and then click on
  the Apply button.

  You can view any of the topics that are displayed by
  double clicking on the topic, or by single clicking
  on the topic and then clicking on the Go To or Visit
  button.