For example, the dog's feces are too dry and there is no water, which may be malnutrition. Usually feed it more fruits and vegetables.
If the dog manure is light in color, it may be a lack of vitamins and minerals. Add some foods with high content of vitamins and trace elements to it when feeding.
If the dog has loose bowels and bloody stool, it is necessary to consult a doctor to see what disease the dog has.