Found this about Gifts:
Gift giving is not just reserved for special occasions; in fact the Vietnamese will find any excuse to give a gift!
Gift giving is a very common practice in both social and business settings. Meet a new friend? Give them a gift! Begin a new job? Buy the boss a gift! Quit your job? Buy the boss another gift! Moving? Buy your friends gifts!
Virtually any public holiday is an occasion to exchange gifts. Gifts need not be elaborate, a book, pen, food, tea, wine and liquor are common gifts. In business, when meeting a new client, try a bottle of Johnny Walker, or a carton of 555 cigarettes, better yet, both!
The Peculiar Vietnamese 
Thank you for sharing the information on gift. According to me occassion is not necessary for giving gift. You can create an occassion for it. BTW your blog is nice. Keep it up the good work.
Question for you…..I had a friend I worked with that was Vietnamese. She was having trouble with the men at work sexually harassing her. I testified on her behalf because I had witnessed this unfortunate event. Some months later, she brought me a gift of a gold ring. I was always curious why she would give me this ring. I thought that it might be in gratitude. Do you know what the significance of this gift is? And, why a gold ring? I thought you might know. Thanks for your help! 🙂