Perhaps you should try some spelling variations:
cam thuc » am thuc, nam thuc, cam thu
cau treo » cau theo, cau tren, cau triet
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
ty mang » ty xang, ty hang, tin mang
mang xa » lang xa, mang may, dang xay
hieu ve » hieu va, hieu van
va danh » va dan, va hanh, dia danh
va dinh » van dinh, va kinh, va tinh
tri cau » tri cac, tri dau, trinh cau
ve cam » ve cham, ve cac, va cam

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 ty mang xa hoi. hieu ve cam thuc ((va danh) or (va dinh)) tri cau treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty mang xa hoi. hieu ve cam thuc ((va danh) OR (va dinh)) tri cau treo.
• Adding a wildcard symbol may retrieve word variants: su sach ty mang xa hoi. hieu ve cam thuc ((va danh) or (va dinh)) tri cau treo*.