The statement is - True.
The gas laws are laws about the gases. They describe and predict the behavior of the gases and are explaining the processes, but what they lack is explanation as to why they had happened.
As most of the definitions, in lot of scientific fields, the gas laws too, give us definitions are rules of how things behave under certain circumstances. But, as most of the other definitions, the gas laws too, lack a proper explanation in them as to why would those processes occur, what triggers them.