a) If a person or a thing is lost, take a square piece of paper, write ASH SHAHEEDO on the 4 corners, and the name of the person or the thing in the middle. At midnight take the paper in your hand and recite this dua 319 times. The lost person or thing will soon be found.
b) To make a disobedient child obedient recite 319 times.
c) If a sick person drinks a glass of water over which this dua has been recited 319 times, sickness will be cure.