Perhaps you should try some spelling variations:
cham thuc » nham thuc, pham thuc, tham thuc
cau tren » cu tren, dau tren, ca tren
van hanh » van thanh, ban hanh, van anh
cuu tre » cua tre, cau treo
te sach » toc sach
va cham » va chat, va tham
hieu va » lieu va, hieu qua
xang xa » lang xa, mang xa, ang xa
y xang » ty xang
va dan » ca dan, va dao, va dau

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te sach y xang xa hoi. hieu va cham thuc ((va dan) or (van hanh)) di ((cuu tre) OR (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y xang xa hoi. hieu va cham thuc ((va dan) OR (van hanh)) di ((cuu tre) OR (cau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y xang xa hoi. hieu va cham thuc ((va dan) or (van hanh)) di ((cuu tre) OR (cau tren))".
• Adding a wildcard symbol may retrieve word variants: te sach y xang xa hoi. hieu va cham thuc ((va dan) or (van hanh)) di ((cuu tre) OR (cau tren))*.