Sure there are some venomous and non-venomous snakes in Krabi, Thailand, but you probably won’t see any at all. We know people who go looking for them, and don’t always find them after spending a few hours in the rainforest looking right where they should be.
They are very good hiders and even if you come to Thailand multiple times, you probably won’t ever see a snake here. There are many reasons for that, but the biggest one is that they don’t like people – Thais regularly kill any snake they see.
Here is a great website about Thailand Snakes. They have information about how to find them, how to avoid them, etc. There are a couple of books – one is a free Ebook you should get if you’ll be staying in Thailand for any length of time and you want to learn about some of the common snakes you might find in your yard or around your home while you are here.