When the short stack is close to 10bb, it is correct to go all in preflop with decent hands. For example, you would push any pair, any ace, and any king. Whether you push certain queens, jacks, etc depends on the kicker and whether it's suited. I don't bother trying to "outplay" my opponent when it's HU and one of us has 10bb because I know I have an edge when I play it push/fold this way.

Can you afford to purchase SnG Power Tools? It'll help you learn proper push/fold for situations like this.