Perhaps you should try some spelling variations:
thanh doi » thanh loi, thanh moi, thanh do
ban thanh » ban hanh, ban hang
thu sach » tu sach, thuat sach, thuoc sach
su sach » so sach, vu sach
cau hoc » cau hoi, cau hoa, cao hoc
doi cua » dai cua, hoi cua
hoc ban » hoc bang, hoc dan, hoc bai
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) or (thu sach)) ky nang xa hoi. ((hieu ve) or (lieu va)) cau hoc ban thanh doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (thu sach)) ky nang xa hoi. ((hieu ve) OR (lieu va)) cau hoc ban thanh doi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (thu sach)) ky nang xa hoi. ((hieu ve) or (lieu va)) cau hoc ban thanh doi cua tre*.