The fork has no labels on the adjusters. I don't know what's what. I checked their website for manuals, and they always mention removable top caps. But as you can see in the photo that these are not removable. I've tried turning them both ways. They only turn, they don't move up/down.
Sorry to say, but those forks do not have much (if anything) you could adjust.
The dials your are seeing are usually associated with more 'base model' coil forks and you would use them to adjust the preload (SAG).
You would adjust the preload for forks to match the rider weight against the suggested preload value. XC preload is typically 15-20%. DH is more. Preload is the initial value by which the forks are depressed in a standing state. Think of it as the bit that extends when the wheel lifts off the ground (in short).
If those dials are still working (they typically seize up or break off on the inside) you can expect them to tighten the coil when turned in the '+' direction. However, experience have tough me that the difference in feel is negligible and in most cases those knobs are actually just for looks. You often find them on budget friendly bikes and often the dials have popped off.