Perhaps you should try some spelling variations:
thanh tung » thanh cong
thuong con » thuong dong, truong cong, thong cong
hieu lang » chieu sang, hieu quang, nhieu tang
hoc hieu » hoc thieu, hoc hien, doc hieu
than cau » toan cau, than cap, thanh chau
phan cau » phan dau, phan cac, phan tu
tung va » trung va, tuong va, dung va
con tan » cong tan, con than, con tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hieu lang - thanh tung va thuong con tan ((than cau) or (phan cau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu lang - thanh tung va thuong con tan ((than cau) OR (phan cau)).
• Adding a wildcard symbol may retrieve word variants: hoc hieu lang - thanh tung va thuong con tan ((than cau) or (phan cau))*.