Perhaps you should try some spelling variations:
cong thanh » dong thanh, cong trinh, cong tan
thanh tran » thanh trang, thanh toan, thanh tra
hien xanh » hien hanh, hien nhanh, chieu xanh
trang tan » trang tuan, trang tai, tang tan
trong tan » trong quan, trong cac, trong ca
dung cong » dung trong
tran tan » tran tuan, tran van, tran thanh
tran cau » tran chau, toan cau, ran cau

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 ((((trang tan) OR (tran tan))) or (trong tan)) dung cong thanh tran cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien xanh - hanh ((((trang tan) OR (tran tan))) OR (trong tan)) dung cong thanh tran cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hien xanh - hanh ((((trang tan) OR (tran tan))) or (trong tan)) dung cong thanh tran cau*".