Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
tu sach » thu sach, su sach, te sach
hieu ve » hieu va, hieu van
cuu tre » cua tre, cau tren, cau treo
ve cac » va cac, vien cac
loc va » hoc va, luc va
vi cuu » vi luu, vinh cuu
x hoi » xa hoi, o hoi, x ho

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) or (thuoc sach)) ky nang x hoi. hieu ve cac ((duc va) or (loc va)) hanh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thuoc sach)) ky nang x hoi. hieu ve cac ((duc va) OR (loc va)) hanh vi cuu tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thuoc sach)) ky nang x hoi. hieu ve cac ((duc va) or (loc va)) hanh vi cuu tre*.