The usual suspects for a low mileage are : Worn out clutch, clogged air filter, low Tyre air pressure, dirty spark plugs, clogged throttle body, adulterated fuel. Isolate each one of them one at a time and try to narrow down on the cause. Getting the car to your regular mech would also help.
BTW, are you facing low/restrained pick-up too?
freakdude.