Perhaps you should try some spelling variations:
cau treo » cau theo, cau tren, cau triet
lanh hai » manh hai, thanh hai, lang chai
cam thuc » nam thuc, cam thu, can thuc
hieu van » hieu va, thien van, lieu va
sach ly » sach y, sach lo, sach ty
va lanh » va lang, va danh, va hanh
ly vang » ly hang, ly van, ly quang
hai cau » hai chau, hai chu, hai hau
vu sach » vu bach, su sach, vu khach
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: vu sach ly vang ((ma hoi) or (xa hoi)). hieu van ((cam thuc) OR (am thuc)) va lanh hai cau treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ly vang ((ma hoi) OR (xa hoi)). hieu van ((cam thuc) OR (am thuc)) va lanh hai cau treo.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ly vang ((ma hoi) or (xa hoi)). hieu van ((cam thuc) OR (am thuc)) va lanh hai cau treo".
• Adding a wildcard symbol may retrieve word variants: vu sach ly vang ((ma hoi) or (xa hoi)). hieu van ((cam thuc) OR (am thuc)) va lanh hai cau treo*.