In 1954, when the communists took over North Vietnam, Dam fled to the south.  He and other monks who immigrated from the North resided and practiced Buddhism in Giac Minh temple in Saigon.

During the Buddhist crisis in 1963, he and many other monks challenged the Diem administration in an attempt to obtain fair treatment for Buddhists. At that time,  South Vietnam's government was Roman Catholic. During the second republic's government in South Vietnam, Dam was a military chaplain with the rank of captain.  The communists defeated the South Vietnamese government in 1975 and put South Vietnam under communist rule. Dam was again forced to flee, this time to the United States.

In the District, he and another monk, Venerable Thich Giac Duc, bought a rundown old church on 16th Street NW and built a Buddhist temple in 1975.  To support himself and the temple, he worked as an electrician. By late 1975, the flow of refugees fleeing Vietnamese communist rule was growing. The refugees were looking to their Buddhist faith to help them rebuild their lives. With the community's support, the two monks purchased a bigger piece of property, also on 16th Street, and built a Vietnamese temple, named Vietnam, in late 1975. 

In 1981, Vietnam temple was renamed Giac Hoang in honor of King Tran Nhan Ton (1258-1308), who in 1293 renounced his monarchy and became a monk at the Truc Lam temple in Yen Tu Mountain, North Vietnam.

Under Dam's leadership,  Giac Hoang blossomed into a religious and cultural center for the Vietnamese Buddhist community in the D.C. area.   During the decades after 1975, he consistently helped many refugees from Vietnam and other countries to settle here and become successful.   On Buddhist celebration days such as Buddha's Birth and Enlightenment, New Year's Eve and the Hungry Ghost festivals, hundreds of Buddhists from not only the D.C. area, but also from as far away as New York, Massachusetts, Pennsylvania, Florida and North Carolina, came to Giac Hoang to take part in the prayer ceremonies that Dam led.

Dam was always willing to help other Buddhist communities in the area. Giac Hoang is a key participant in the International Buddhist Committee's annual Visakha celebration, a multicultural Buddhist celebration of the Buddha's Birth and Enlightenment.  Hundreds of Vietnamese, Cambodian, Thai, Tibetan, Sri Lankan, Laotian, Indian and American Buddhist families from around D.C. attend the joyful celebration.

On two occasions, Dam generously hosted a major tour of Buddhist holy relics organized by the foundation for the Preservation of the Mahayana Tradition, a Tibetan Buddhist organization.

Dam is remembered by all who knew him as a very kind and humble mentor. Several times,  he squeezed more rooms into Giac Hoang's living quarters for  monks, nuns or lay persons who needed shelter. He would visit any Buddhist family to share their sorrow of losing a loved one and bless them. Wherever he went, he brought the simple gift of love and peace. In keeping with the Buddhist tradition, for the next seven weeks, visitors will come to Giac Hoang temple to pray for Dam.