You need to understand that god's identity is different that the world you live in. We are limited by space, time and place. But when it comes to god. THERE IS NOTHING LIKE HIM. He is everywhere. He can sense but without the help of limps, like us humans. He is strong, but that does not mean he has big muscle of huge volume, like we describe a strong person in our world. His existence is different from our existence. We are limited, he is not limited.
Another thing is that god does not need to be physically seen. The reason why is that if he is physically seen, everyone will be forced to believe in him, but if our sight can not see him, we would have to use our logic and look at his creation of us and of the universe.