Perhaps you should try some spelling variations:
chu treo » cau treo, cu tren, cau tren
hieu van » hieu va, thien van, lieu va
danh hai » dang hai, lanh hai, manh hai
cam thuc » am thuc, nam thuc, cam thu
nang ma » tang ma, sang ma, mang may
sach ly » sach lo, sach ty, sach hay
van cam » van nam, van lam, van cau
thuc va » thuc vat, thuc dan, thuc day
va danh » va dinh, va dan, va hanh
hai chu » hai chau, hoi chu, hai chi

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