Bro 99% of the teaching jobs in vietnam are on facebook. Viets fucking love facebook.
At the end of the day most of them are the same. If you end up posted at a good school where the teachers enforce standards and the kids are well behaved, its cruisy. If you end up at one where the teachers dont care and the kids are all retarded, which is a lot of them, you will want to commit genocide (in minecraft)
I would recommend getting in contact with this guy/buying his service.
https://www.youtube.com/@rebornabroad/featured
Unfortunately he nuked his previous youtube channel which is a crying shame since it was the most abundant, no bullshit, ubiquitous vlog resource of everything about working in vietnam. However he still runs the service where he hooks you up with everyone you would ever need - visa agents (most important), rental people, employers and so on.