Xe Lửa is "fire car" or train, but why is a pho place calling itself "Train"? For its speed. In the early 70's, the first Train pho joint opened in Saigon, then not long after, another place outdid this by calling itself "Airplane," meaning it could serve your pho even faster. Now there are Train and Airplane pho restaurants in half a dozen countries, at least.
As for this place's claim to serve Thai food, that's pretty funny, considering the fact there are almost no Thai restaurants in all of Vietnam. Vietnamese know next to nothing about Thai food. Just because two countries are close to each other does not mean they are familiar with each other's culture. (If you go to England, however, you'll find Thai restaurants all over, even in tiny villages. Also, French restaurants are extremely rare in Italy, but Italian restaurants are all over France.)