Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
dinh hai » dinh thai, tinh hai, dinh ha
sach ty » sach tu, xach tay, sach hay
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
cac lop » cac hop, cac loai
va dinh » van dinh, va kinh, va tinh
hai cua » thai cua, dai cua, hoi cua
cua tre » cua te, cuu tre, cua triet
lop va » lap va, hop va, nop va

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

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