I've bought a new computer recently and was disappointed, because Maple uses only 25% of that processor (my old computer used 99% of CPU).

I have Intel Core i5 750 processor (it has 4 kernels).
From the Screenshot you can see that It uses only 25%, but not because it uses only one kernel (it uses all 4 kernels).

If I open two Maple instances and run the same program on all of them at once then I get 50% of CPU used.

The question is:
how to force to use Multi-Kernel processor to work at 90% (if needed) with one single Maple program?

It seems that this isn't a limitation to Maple, but for all other programs as well.
For example,

How to execute expression when creating a function?
(before creating it, inside it)