steal = robar, for objects that you physically take.
to steal sb = to kidnap
The verb to steal takes as object the thing that was taken from the person who was robbed.
I stole a ring from Lisa.
To rob somebody
rob = asaltar, for people, places, etc.
But - To rob a bank (=> A bank robbery)
The verb to rob takes as object the person who owned the thing that was stolen.
I robbed Lisa of a ring.
My watch was stolen yesterday
Someone robbed me in the street
They robbed the bank last week
He stole my wallet
I have been robbed
But if you still find it confusing, what follows can be quite clarifying...
When you rob a man, you steal his watch.
When you rob a bank, you steal the money.
Si dices "to steal a car" significa "robar un coche", vamos, llevárselo enterito...
En cambio "to rob a car" sería abrirlo y robar la minicadena, cosillas que tengas dentro... Tal vez te quedes con un cristal roto, pero el coche permanece en su sitio.
Finally, this is a very clear explanation of the differences among theft, burglary and robbery:
If someone gets into a jewellery and steals inconspicuously and without
violence a ring that the jeweller had left on a glass cabinet, that is
called THEFT. If somebody gets in that same shop violently, carrying a
weapon and threatening, then it's a ROBBERY. And if a person decides
to sneak inside the jewellery at night, and steals several valuable
objects, in that case it would be a BURGLARY.