What is the function of peach wooden sword?

Family members have bad luck for a while, and they always have bad luck; Or family members are sick and can't be cured for a long time. In this case, you have to put the peach wooden sword on the wall opposite the door of your house. Some shops are bloodbath, or houses are near the cemetery. In this case, peach swords must be placed on both sides of the gate. It can be said that the peach wooden sword is used to ward off evil spirits in the town house here.