Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
trinh tuan » trinh quan, trinh toan, trinh luan
cong thanh » dong thanh, cong tan, truong thanh
hien xanh » hien hanh, hien nhanh, chieu xanh
tuan dung » tuan duong, tran dung, tan dung
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 trinh tuan dung ((cong thanh) or (cong trinh)) tran cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien xanh - hanh trinh tuan dung ((cong thanh) OR (cong trinh)) tran cau*.