Bossing,

You can try checking the possible causes:
  1. Defective PCV valve
  2. Dirty Carburator (Floater valve might be dirty or clogged)
  3. Clogged Fuel filter
  4. Incorrect ignition Timing
Check your Spark plugs. Try removing and check its condition, does it show black dry deposits? If yes, then you're burning too much fuel.

You might need the assistance of your trusted mechanic to check your vehicle.

Thanks