Are you sure that he is not seeing them vs. being very into whatever else he's doing and not caring to stop that in order to look for whatever you want him to get? We notice that at times with our DS.
What was the treatment for his lazy eye? Lazy eye can be a symptom of severe farsightedness. We went through three eye doctors before we learned DS is severely farsighted. The last one is very knowledgeable about kid's eye issues.
BTW, we were amazed to learn how bad the farsightedness was, given that he read constanstly pretty early, was great at complex puzzles, etc.
He's trying really hard to look for whatever it is he's supposed to bring / find. It might be something very obvious and he's right next to it and still doesn't notice it.
