I was surprised to find out that Oak trees can actually grow in Thailand. I thought it would be far too hot, and maybe too rainy. Maybe it is a special species? Or there is a particular region / soil or something...

Are there many other fruiting trees that grow both in the UK and Thailand?

Hope you don't mind if I move this into the pets, vets section which is also supposed to include gardening!

I would think many temperate trees that do not require alot of chilling would grow well in Thailand (northern).

The problem with most temperate fruit trees is that they require a certain number of "chilling hours" ie days with the temp under a certain number. I dont' think that even the north would provide enough chilling hours for most things like apples but they are making new improvements in fruit all the time so they may come up with a low chilling requirement apple or pear some day!