Dear Dora,
I am writing to say thank you for making such excellent arrangements for my rail travel to Ho Chi Minh City and the engagement of Mr Vu Bac Son as my guide. I would like you to pass on my particular appreciation to him. He was attentive, knowledgeable and good company from the moment he and the driver met me off the train at 05:20 until the time they dropped me off at the airport at 15:00. I shall certainly recommend your company to anyone who asks my advice about travel in Vietnam.
With warm wishes,
Richard