Perhaps you should try some spelling variations:
chau treo » cau treo, cau theo, chau tho
cam thuc » am thuc, nam thuc, cam thu
hai chau » lai chau, ha chau, hat chau
hieu van » hieu va, thien van, lieu va
va hanh » van hanh, va thanh, ban hanh
va danh » va dinh, va dan, dia danh
su sach » so sach, vu sach
sach ly » sach y, sach lo, sach ty
nang ma » tang ma, sang ma, mang may
van cam » van nam, van lam, van cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ly ((nang ma) or (nang cao)) hoi. hieu van cam thuc ((va danh) OR (va hanh)) hai chau treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ly ((nang ma) OR (nang cao)) hoi. hieu van cam thuc ((va danh) OR (va hanh)) hai chau treo.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ly ((nang ma) or (nang cao)) hoi. hieu van cam thuc ((va danh) OR (va hanh)) hai chau treo".
• Adding a wildcard symbol may retrieve word variants: su sach ly ((nang ma) or (nang cao)) hoi. hieu van cam thuc ((va danh) OR (va hanh)) hai chau treo*.