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: 
Roughly speaking, electric fields push and pull charges, while magnetic fields cause charges to loop around (by 'loop around' I'm saying that the magnetic fields cause the charges to accelerate at a right angle to their direction of motion). 

Since light doesn't have an electric charge, there is nothing for electric fields to push or pull and nothing for magnetic fields to loop around. 

If we just look at the classical case, then there is no direct interaction between magnetic fields and the electromagnetic wave. It's a little bit like how most waves can just pass right through each other without changing each other.

That being said, if magnetic fields are crazy intense, (say the magnetic fields near the surface of a magnetic pole of a neutron star) then there are some higher-order quantum effects that come into play.

This is due to the possibility that the photon splits into a virtual electron-positron pair and then recombines. An intense magnetic field could interact with the virtual pair and have an effect. 

For instance, depending on how the virtual pair is aligned with the magnetic field, the energy level would be higher or lower, and this has an effect on how much of a contribution this possibility has. 

This is called the [Euler-Heisenberg interaction](https://en.wikipedia.org/wiki/Euler%E2%80%93Heisenberg_Lagrangian).
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>