How do you use the item finder on Pokemon Diamond?

[pokemon_rock]

I dont know how to use it

[Shanaweh]

Just tap on the poketch with your stylus. If there is an item in the area you are, the circle created will flash. If you are near the item, you'll see a dot on the screen where the item is. Each division on the axis represent one step with your character so you'll know exactly where the item is.

I hope this will help you.