I HEARD THERE WAS A BUSINESS AIR THAT FLIES DIRECT TO XIAN, ANY TRUTH TO THAT?

There is no direct flight from Thailand to Xian, so you still need to fly to Shanghai directly first and then fly to Xian. There is a flight from Bangkok to Shanghai, which can catch the last fligt from Shanghai to Xian and you may book that one. You can refer to https://www.travelchinaguide.com/china-flights/ to search for a suitable flight to China and hope you have a good trip in Xian.