Yes, many if not most Thai dishes can be made vegetarian/vegan if you learn how to say the specific ingredients you want and don't want in Thai. 'Mai sai gai' (without chicken), 'mai sai kai' (without egg), etc. If you know a little about the dish you're ordering you will know what they usually put in there, and therefore what to say you don't want in there. Usually I ask first if they have tofu, 'mee tao-hoo mai kha?' then from there either order a tofu version of what I want, or a vegetable version, 'pak'. For example, 'ow pad see ew pak mai sai kai', 'want pad see ew vegetable without egg'. Basically if you learn some Thai it's super easy. Or you could just use Google translate. Either way I've found it's essential to be specific with the ingredients you want and don't want. ☺️