[Meaning] If set, the operation searches from the end of the current selection to the end of the document. If not set, the operation searches from the end of the current selection to the beginning of the document. [Value] 
FR_DOWN
F R _ D O W N
F R _ M A T C H A L E F H A M Z A
F R _ M A T C H C A S E
F R _ M A T C H D I A C
F R _ M A T C H K A S H I D A
F R _ W H O L E W O R D