Question: As light is electromagnetic radiation. Then why I don't see any magnet bending light wave? Or why light doesn't diffract whenever it passes by a live wire?

Answer: 
In vacuum electromagnetic fields obey superposition to a very high degree of accuracy. A magnetic field does not have any effect on light. Light in material media *can* be affected by a magnetic field. This is known as the [Kerr effect](https://en.wikipedia.org/wiki/Kerr_effect).

As for current carrying wires, these reflect and diffract electromagnetic waves like any metallic or dielectric object. This is why you see them. However, there is no effect of the current until the wire heats up.
In classical physics, electromagnetic fields and waves are additive so nothing can happen in vacuum between electromagnetic fields. They don't see each other.

In quantum physics, photons theoretically DO interact. The effect is rather small even in high-energy experiments, so don't expect some visible distortion with visible light and an iron magnet.

<https://en.wikipedia.org/wiki/Two-photon_physics>