First of all, you have to go to Shkodra. You can i take the airplane to Tirana, then go to Shkodra with a rent-a-car; ii take the airplane to Tirana, then go to Shkodra with a taxi or bus and then taking a rent-a-car in Shkodra; iii from Montenegro, you can enter Albania through Muriqan, go to Shkodra and use your car to go to Thethi.From Shkodra to Thethi, you go through Koplik. Note that there are 3 ways to go to Koplik; ask in Shkodra for the shortest. Shkoder-Koplik is around 20 minutes, and Koplik-Thethi Village is around 1 h 20 min. However, note that you'll need a good car to go to Thethi, preferably a Jeep. If you have an old or small, or even if your car is good but not a Jeep, its the best to rent a Jeep at the local stores, as they are not expensive, but they are very safe for your security.