Deliver是送货的意思，而convey则是传递的意思，区别可以从以下例子看出：

I will deliver this to you by hands, but this product will be conveyed to you by production belt, as it is too heavy for me. 这个我会亲手给你，但是这个产品会通过生产皮带运送给你，因为它对我来说太重了。