Thanks for your help.
I know it is not easy but possible. I have a friend who worked in Singapore as trainee in IT. But of course it seems easier to find a position in an international company which has an office in thaïland.
Do not let hope walk away! Here in France, we can ask for a list of french companies based in thaïland (or having offices in) or other countries around the world. Maybe you can try this too: big companies like banks, insurance (...) have office there?
Good luck to you too! If I find something I will tell you.