I think the plant is called Euphorbia milii or the crown of thorns. It looks a bit like cactus and succulents. You can check if it has quite some thorns. If yes, then I am sure it is the crown of thorns. It's originally from Madagascar. But I saw it a lot too in South East Asia. People would plant them in pots. They are not difficult to care and enjoy lots of sun exposure. The leaves contain white-ish sap that might cause irritation to human skin.

You may want to read this very informative article about the plant: https://steemit.com/petals/@sardrt/2bevsk-euphorbia-milii-thorn-of-christ-photos-by-sard-rt by @sardrt