Perhaps you should try some spelling variations:
thien van » thi van
cau treo » cau theo, cau tren, cau triet
danh hai » dang hai, lanh hai, manh hai
cam thuc » am thuc, nam thuc, cam thu
hieu van » hieu va, lieu va, hieu ve
nang ma » tang ma, sang ma, nang cao
sach ly » sach y, sach ty, sach hay
sach lo » sach dao, sach doi, sach hoi
thuc va » thuc vat, thuc dan, thuc day
va danh » va dinh, va dan, va hanh
hai cau » hai chau, hai chu, hai hau
ma hoi » mai hoi, xa hoi, ma hoa

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