Perhaps you should try some spelling variations:
ban banh » ban hanh, ban anh, ban danh
tu sach » thu sach, su sach, te sach
cua tre » cua te, cuu tre, cua triet
duc ban » duc tan, duc van, dua ban
cam duc » cam xuc, cao duc, pham duc
hieu va » lieu va, hieu qua
tu nang » tru nang, tu nano, tu lang
tu nong » tu dong, tu cong, tu tong
va cam » va cham, va cac, va cao
banh d » anh d, binh d
cua su » qua su
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 ((tu nang) OR (tu nong)) o hai. hieu va cam duc ban banh d ((cua tre) or (cua su))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((tu nang) OR (tu nong)) o hai. hieu va cam duc ban banh d ((cua tre) OR (cua su)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((tu nang) OR (tu nong)) o hai. hieu va cam duc ban banh d ((cua tre) or (cua su))".
• Adding a wildcard symbol may retrieve word variants: tu sach ((tu nang) OR (tu nong)) o hai. hieu va cam duc ban banh d ((cua tre) or (cua su))*.