Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
sach thu » sach thue, sach thieu, sach tham
hanh doc » hanh duoc, nhanh doc, anh doc
ban hanh » ban hang
cua tre » cua te, cuu tre, dua tren
duc ban » duc tan, duc van, dua ban
cam duc » cam xuc, cao duc, pham duc
hieu va » lieu va, hieu qua
nang o » nang co, nang ho, nang ro
va cam » va cham, va cac, va cao
o hai » co hai, so hai, o lai

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach thu) or (sach y)) nang o hai. hieu va cam duc ban hanh doc ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach thu) OR (sach y)) nang o hai. hieu va cam duc ban hanh doc ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach thu) or (sach y)) nang o hai. hieu va cam duc ban hanh doc ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: tu ((sach thu) or (sach y)) nang o hai. hieu va cam duc ban hanh doc ((cua tre) OR (cua triet))*.