Beside his job as a lecturer in Vietnam National University (teaching zoology), he has guided as a birding tour guide for many birdwatcher from many countries in the world.

At first he guided with free of charge to merely share his experience and help birdwatchers who come to Vietnam for the first time and also to improve his background on ornithology. From the year of 2000 to date, he has done many surveys of bird and mammal, especially for conservation projects that supported by NGOs such as Birdlife International, World Wild Fund for Nature (WWF) and International Crane Foundation (ICF).

He also is founder and general manager of WildTour Company, the first and unique tour organizer concentrating on birding and ecotourism in Vietnam.