Perhaps you should try some spelling variations:
cham thuc » nham thuc, pham thuc, tham thuc
cua viet » hoa viet, cua vat, cua dieu
thanh ve » hanh ve, thanh va, thanh vien
va thanh » gia thanh, ban thanh, va tinh
te sach » toc sach
sach ty » sach y, sach tu, sach thu
thuc va » thuc vat, thuc dan, thuc day
ve cham » va cham, ve chat, vu cham
hieu ve » hieu va, hieu van
tang ha » lang ha, tang ma, trung ha
xang ha » lang ha, dang ha, hang ha
ca viet » va viet, co viet, hoa viet

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 ty ((xang ha) or (tang ha)) hoi. hieu ve cham thuc va thanh ve ((cua viet) OR (ca viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty ((xang ha) OR (tang ha)) hoi. hieu ve cham thuc va thanh ve ((cua viet) OR (ca viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty ((xang ha) or (tang ha)) hoi. hieu ve cham thuc va thanh ve ((cua viet) OR (ca viet))".
• Adding a wildcard symbol may retrieve word variants: te sach ty ((xang ha) or (tang ha)) hoi. hieu ve cham thuc va thanh ve ((cua viet) OR (ca viet))*.