Perhaps you should try some spelling variations:
bien quang » dien quang, trien quang, lien quan
thong cong » trong cong, tong cong, thong thong
hien xanh » hien hanh, hien nhanh, chieu xanh
tinh quan » tinh quang, trinh quan, tin quan
cong tan » cong tac, cong san, cong thanh
tan than » tan thanh, tan tran, ban than
than cau » toan cau, phan cau, than cap

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hien xanh - hanh ((tinh quan) or (bien quang)) thong cong tan than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien xanh - hanh ((tinh quan) OR (bien quang)) thong cong tan than cau*.