code: function getSearchRange( isDefault ) {
  				var searchRange,
  					sel = editor.getSelection(),
  					editable = editor.editable();
  
  				if ( sel && !isDefault ) {
  					searchRange = sel.getRanges()[ 0 ].clone();
  					searchRange.collapse( true );
  				} else {
  					searchRange = editor.createRange();
  					searchRange.setStartAt( editable, CKEDITOR.POSITION_AFTER_START );
  				}
  				searchRange.setEndAt( editable, CKEDITOR.POSITION_BEFORE_END );
  				return searchRange;
  			}
docs: The range in which find/replace happened, receive from user selection prior.