I'm not sure I understand your question, but
- you are allowed four flight segments in Asia and the fact that your itinerary starts and ends in Asia does not change that
- these will have to be either before your first intercontinental flight, or after the last intercontinental flight, or a mix of both
- as Jerry pointed out, you are allowed only two stopovers in your continent of origin, and you cannot travel via your country of origin (so something like TYO-HKG-xTYO-HNL... would not be valid)
What about NRT-HKG-USA-Europe-Asia(3 segments)?
Yes, that would be valid.