OBDII is a standard interface, and a possibility of car manufacturers to make their cars (at least in part) compatible. So you can just read the values that manufacturer implemented into OBDII layer.
On the other hand, every car has its own comminication interface (newer the car higher the possibility for CAN-bus).
That system is able to provide all the informations. Car (or brand)-dependent specific program is the keyword for you.
What car do you have?