Setting Position while Controlling Velocity via mavros

Hello everybody,
I want to set some positions for the drone to follow, but I would like to control velocity as well. As far as I searched mavros/setpoint_raw (I will use local, working on Gazebo now) is what I needed. However, when I specify some values for position, velocity, acceleration, yaw and yaw rate parameters, nothing happens. I think “mask” is critical.
Does anyone have a code or explanation regarding this?
Thank you!