Could you tell me what is the problem with a child's eyes if it was dropping lot of tears and lot of dust forming in lids?

Possible Pink Eye. "Child's eyes...dropping lots of tears...dust forming in lids". Your description is consistent with eye discharge. In children, this is commonly caused by upper respiratory infections due to bacteria or viruses and is contagious. Antibiotic treatment may be required. See your child's doctor for correct diagnosis and treatment.