Please name a movie.

The plot was about a young man who went to Tibet. The people there were simple and honest. The young man got along well with them and established a deep relationship with them. However, after the young man returned, his father went to attack that place. No matter how the young man persuaded his father, he could not persuade him. In the end, there were many casualties due to the invasion. He remembered that there was a lighter in the plot. Young people learned how to use flint to light fire, while Tibetans learned how to use lighters. It was a very old movie.