Why we can't see our Sun as it was a few years ago? Our Sun is orbiting the center of the Milky Way galaxy. So many years ago, it was at a different location from where it is now.
In addition, we are observing stars and exoplanets as they were many years ago, for example stars like Sirius.. 

In this case, why can't we see our own Sun in its orbital path a few hundred years back. 
Is there any specific reason why we can't see/observe our Sun from the past?
Our Sun moves through the galaxy much slower than light does. So the light that was emitted last year by the Sun is already very far away from the Earth. Therefore, we don't receive any light from (i.e. we don't see) the Sun as is was last year. 

As an analogy, image walking along and shooting bullets in all directions. The bullets are going much faster than you can go by walking, so you won't ever get hit by your own bullets. But someone walking next to you can get hit by the bullets you are shooting out.