southeastastra - Long-sightedness? So your DS can see far (reads blackboard, subtitles at movies, etc), but can't see near (can't read book in his hand).
Imagine the eye as a sphere. Now press from front and back. That is what his eye looks like. Because the distance from cornea to retina (front to back) is shorter than usual, images focus behind his retina rather than on it.
No drops or medication is going to change the shape of his eye and hence his far sightedness, but the correct prescription glasses or contact lenses will help him see better.