Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh ban » thanh san, thanh van, thanh bac
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
nang xa » nang x, lang xa, nang ma
hieu va » lieu va
ban cua » ban quan
cua tre » cua te, cuu tre, cua triet

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 ty nang xa hoi. ((hieu va) or (hieu qua)) ((tao duoc) or (giao duc)) ban thanh ban cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty nang xa hoi. ((hieu va) OR (hieu qua)) ((tao duoc) OR (giao duc)) ban thanh ban cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach ty nang xa hoi. ((hieu va) or (hieu qua)) ((tao duoc) or (giao duc)) ban thanh ban cua tre*.