Perhaps you should try some spelling variations:
cang thang » cong thanh, dang thanh
cong vang » cong lang, cong quang, cong ngang
nhanh cau » nhanh cay, thanh chau, nhanh ha
hoc hieu » hoc thieu, doc hieu, hoc dieu
thang va » hang va, trang va, thong va
cong van » cong san, song van, cong tan
va dung » van dung, va duong, vat dung

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc hieu) OR (hoc hien)) manh - cang thang va dung ((cong van) OR (cong vang)) nhanh cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc hieu) or (hoc hien)) manh - cang thang va dung ((cong van) OR (cong vang)) nhanh cau~".
• Adding a wildcard symbol may retrieve word variants: ((hoc hieu) or (hoc hien)) manh - cang thang va dung ((cong van) OR (cong vang)) nhanh cau*.