Perhaps you should try some spelling variations:
cong thanh » cong trinh, cong tan, truong thanh
thuoc dieu » thuc dieu, hoc dieu, thuat dieu
dong thanh » truong thanh
hanh tang » hanh trang, hanh mang, hanh tung
anh tang » anh bang, anh dang, anh nang
va hang » van hang, va nang, va lang
tra cau » tra sau, ta cau, tra cuu

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc dieu hanh - ((hanh tang) or (anh tang)) va hang ((cong thanh) OR (dong thanh)) tra cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc dieu hanh - ((hanh tang) OR (anh tang)) va hang ((cong thanh) OR (dong thanh)) tra cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc dieu hanh - ((hanh tang) or (anh tang)) va hang ((cong thanh) OR (dong thanh)) tra cau".
• Adding a wildcard symbol may retrieve word variants: thuoc dieu hanh - ((hanh tang) or (anh tang)) va hang ((cong thanh) OR (dong thanh)) tra cau*.