Go through your results for flights to Ubon Ratchathani in Thailand with Netflights. Although Thai Airways International usually has the best prices, it's best to double check what's available for your travel dates.
If these flights are too expensive, try searching for a different time of year. So if your dates are flexible, consider looking at different times of year.
But if you're struggling to find flights to Ubon Ratchathani that work for you, try looking at other airports in Thailand.
You can also broaden your search by looking at more than one departure airport. Have a look around – you might be able to save by flying from a different airport or city.