Article in English: If you are at a restaurant, wait until everybody’s meal has arrived before you start to eat. When at a dinner party, wait for the host/hostess to unfold his or her napkin and begin eating. It is not only rude, it can actually ruin other peoples’ appetites.  Also avoid burping, smacking your lips, or fidgeting at the dinner table. If you have to cough or sneeze at the table, be sure to cover your mouth with a napkin. If you need to get up from the table to go to the restroom, let others know where you are going. Not only will it disturb other patrons if you are in a restaurant, it is disrespectful to the person/people you are eating with, especially if one of them has cooked the meal for you. Wait until the end of the meal to make phone calls. Turn off or silence your phone during formal dinners. This rule applies only when you are actually eating. If the food has not yet arrived, or if you are sitting at a table drinking water or other beverages, then it is acceptable to rest your elbows on the table. Not only is it healthier than taking huge bites, it will give you the opportunity to quickly chew and swallow your food if somebody asks you a question when you have food in your mouth. Nothing is more frustrating (and embarrassing) than having somebody ask you a question right after you have taken a huge bite of food! Otherwise, ask somebody to please hand it to you. Always pass the salt and pepper shaker together, even if the person only asks for one of them. These items are meant to be kept together at all times. Clean your fingers or blot your lips when necessary. Be sure to thank the waiter/waitress if you are at a restaurant, and thank the host/hostess if you are at a dinner party. Compliment the food when dining with the person who has cooked it.

Summary in Vietnamese:
Chưa ăn khi bữa ăn chưa bắt đầu. Không nói chuyện khi thức ăn còn trong miệng. Nói xin phép khi cần thiết. Không nhắn tin hoặc gọi điện thoại. Không đặt khuỷu tay trên bàn ăn. Cắt thức ăn thành miếng nhỏ vừa miệng. Chỉ lấy những thứ ở trong tầm tay của bạn. Nhớ dùng khăn ăn. Nên cảm ơn đúng cách.