Make sure to travel with alot of package food and if visiting county with different language please check with any native (if you know) the correct and exact pronunciation of word Vegitarian in their language.. i hope this helps
As i am Jain I always carry some Indian foods with me, lower number of clothes and othe i carry food more. also in most of the countries you will get Swaminarayan food and many indian vegan or shop which you have to find newby in any country you are visiting. if traveling with any tour company then they will arrange all for you.
While planning your travel abroad plan your veg meal too. With availability of many ready made food, carry the food you like very much. Be any country it’s not devoid of bakery, French fries, salads and some veg curries. Also survey online and enquire in advance about Indian restraunants who serve vegetarian food. Always keep stock of Maggie, chips, reward to cook pasta, chocolates, biscuits in your travel bag. When I travelled to Europe being a vegetarian had enquired a lot about veg hotels, who serve veg food. Also I packed enough ready to make vegetarian food.