Perhaps you should try some spelling variations:
hanh hai » thanh hai, nhanh hai, hang hai
ban hanh » ban hang
sach thu » sach thue, sach tham, cach thuc
hai cua » thai cua, dai cua, hoi cua
duc ban » duc tan, duc van, dua ban
cac duc » cac du, cao duc, cac dac
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
bang va » hang va, ban va, trang va
bang xa » lang xa, mang xa, ang xa

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

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