2011 VW Touran TDI verbraucht viel Diesel.

I'm new here. I just got a VW Touran 2011 TDI at 110,000km and the car is really nice and stuff, but I have a problem with how it uses diesel. I understand diesel is good for longer distances, but I literally see the fuel clock moving when I do a few car trips. I made a 44km trip and the tick shifted a beam, which in my opinion means a lot for a diesel engine in a 2011 model. I may not go into details because I do not know them, but I had a gasoline car and did not consume so much fuel. Can someone please tell me what the problem could be? Before I bought the car, I took it to the garage to check on it, and the mechanic checked it and said that the car is in top condition. I had expected more fuel consumption from this model.