The southeast door of the countryside is open, but the front door is empty, facing the crops. Why?

The southeast door of the countryside is open, but the front door is empty, facing the crops. Why? Congratulations! If the front door is empty and flat, that's where the treasure is piled up. "Dalongdong will certainly be able to accommodate thousands of troops in front of the door." This is the wisdom in Feng Shui books. Cropland and geomantic omen have always been regarded as granaries, and a large area of cropland is also a big granary. The front door is empty, which is a treasure land and a granary.