Library /sys$common/syshlp/cms$dw_help.hlb OCC, Oc otb  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  The Others button controls occlusion of other objects,
  including the element list, the group list, the class
  list, library attributes, history, and commands.

  When this button is activated, CMS searches for and acts
  upon the first occurrence of the object (or objects) in
  the library search list.

  If this button is off, CMS acts upon each occurrence of
  the object or objects found in the library search list.