What they were interested in knowing were the types of dimensions that made up the world. Unfortunately, the layers of the world were all they could see currently. They didn't have the ability to see beyond the material plane.
It may not be that they couldn't see it. It could also be that they could see it, but they couldn't understand what they were seeing in their current state. They didn't have the current tools to experience the other dimensions.
They couldn't leave the material dimension either. Space wasn't constraining them anymore. But they simply lacked the ability to move across dimensions.
It was as if they were carried from the land and dropped into an ocean. As land creatures, they simply didn't have the tools required to survive in the ocean.
