If you were in a Jedi vs sith fight, I don't think you'd really have the time or intuition to do so, unless the right situation presented itself.
I'd imagine you'd be more inclined to force throw an object at someone more as a distraction than as an actual weapon. The time it would take to force push poison or acid or something at your opponent could better be spen simply knocking them down or off a cliff or against the wall where you can finish them off with your light saber.
And as for just particularly small objects, again I feel like you'd be better off just using a blaster. The exception might be force pushing lots of small debris like a shotgun, but I'd bet there's some kind of blaster shotgun equivalent you could use.