According to the traditional culture of China, a few walnuts under the pillow can ward off evil spirits and drive away ominous qi. Walnut itself has powerful energy, so it can absorb evil spirits and help protect the health and happiness of family members. It has also been suggested that the number of walnuts under the pillow should be odd, not more than nine at most, because nine is a pure yin auspicious number, which can ward off evil spirits more effectively. Solemnly declare: the answer is for reference only, please don't be blindly superstitious.
Since ancient times, people have kept walnuts at home or carried them with them to ward off evil spirits, which is said to drive away evil spirits and bring good luck. Emperor Qianlong once described it as "exorcising evil spirits and avoiding disasters to ensure peace".