Got cheated with purchase of used car

I was looking for a used car for my personnel use. I didn’t want to buy from used car dealers because I heard that they don’t tell true story of the car. My personnel choice was to buy it from a private person. I explored Facebook market place and found a listing where the car was described as privately held with no issues. I visited the seller house and asked questions on car history and the mileage where they assured everything was ok and allowed us to have a short test drive. Since I don’t know much about the cars I trusted them and bought the car considering them as the private seller. First they asked me to pay by cash but then agreed for online transfers because of my request. They arranged 2 different bank accounts to get the payment transferred, which they seemed to be worried about . After driving the car to home for 25 km, we noticed problem with the clutch , radiator fan, air conditioner. We took it to nearby mechanic where he confirmed that over reading of total run is tampered and the car could be driven more than twice if that reading . Also the original parts were replaced with poor quality. I called the seller back and they denied to take any responsibility claiming we had tested the car and they don’t know anything now. They also threatened saying they are dealers of the car who sell around more than 50 cars a month and no one could do anything to them . I feel cheated that I trusted them as a private party but they were the dealers selling the cars from their home living room and basement parking. What can I do and expose them on how they cheat the people presenting themselves as private person.