Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
lanh hai » manh hai, thanh hai, lang chai
dan lanh » dan canh, dan hanh, dat lanh
thuc dan » thuc hanh, hoc dan, thuc vat
cam thuc » am thuc, nam thuc, cam thu
hieu van » hieu va, thien van, lieu va
hai cau » hai chau, hai chu, hai hau
van cam » van nam, van lam, van cau
sach ly » sach y, sach lo, sach hay
sach ty » sach y, sach tu, sach thu
ma hoi » mai hoi, ma hoa, me hoi

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