How do I give different piano clefs different dynamics?

When I try to give let's say the treble clef p < mf, and let the bass clef stay the same, both the treble and bass clef go down to p and crescendo. Another example would be if I tried to make the treble clef forte and the bass clef mezzoforte, both would stay the same at whichever dynamic I most recently placed. So is there any way to give the two parts different dynamics, or is it just part of the program to make them stay the same because it's just one instrument. Or is there an obvious feature that I don't know about because I'm slow.