Ceasing fire?

I've been invested in Israeli victories since 1967 (Moshe Dayan with his eye patch!) and with a Ukrainian victory since 2022 (Zelensky saying that he needed "ammo, not a ride" out of Kyiv!). But Cambodia? Thailand? Well, it's nice that they've ceased firing, but what were they firing about in the first place?

I changed planes in Bangkok one time, and had to make a flying wedge with a German doctor and an English nurse to get on the plane to Rangoon. I enjoyed the airport, which had cows grazing between the runways, but not so much that I would take sides in a Thai-Cambodian war. They both seem like nice countries. Why would they go to war? It's as bewildering as Luxembourg invading Belgium!