Perhaps you should try some spelling variations:
sach thue » sach thieu, sach tham, cach thuc
pham thuc » phap thuc, pham chuc, nham thuc
sach thu » sach thieu, sach tham, cach thuc
hanh va » hang va, hanh vi
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
va pham » van pham, va phat, va phap
lai hoi » dai hoi, lai hoa, lai roi
hieu va » lieu va, hieu qua
mai hoi » mai khoi, dai hoi, mai doi
cua tre » cua te, cuu tre, cua triet
va cua » va chua, via cua, ca cua

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 thu) OR (sach thue)) hang ((mai hoi) or (lai hoi)). hieu va pham thuc va hanh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach thu) OR (sach thue)) hang ((mai hoi) OR (lai hoi)). hieu va pham thuc va hanh va cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach thu) OR (sach thue)) hang ((mai hoi) or (lai hoi)). hieu va pham thuc va hanh va cua tre*".