Problem after buying a car.

Hello. Hope here someone can help me. I bought a car yesterday from private. Tüv had expired in July. According to the seller a few crossbars would be made. Therefore for me no problem. So yesterday the car fetched. On the return drive after about 200 km motor control lamp. Well, who knows maybe the installed gas system swallowed itself. Errors deleted and further. Another 200 km further again warning lamp. Well Nachm tüv ehh goes to the workshop. So today to the tuv. : Not to exist, whole engine oily, crankshaftsimmering leaks and Lambda regulation does not work. So I called the seller. He says he knows nothing about nothing… He refers to purchase contract entry -> bought as seen In the purchase contract, however, there are defects: none of this but just a few repaintings. So I called the workshop where the seller has always taken the car. So I am told that the car was presented to the tv in May and the defects that I have already been known and therefore the car did not get a tuv. I asked the sellers explicitly about problems like oil loss and whether the gas system works perfectly. Was everything answered with no problems. I looked under the car but it is relatively deep so that I could not see any oil and the motor control lamp was also not up to. Is there thus fraudulent deception? Greetings