Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
ta thanh » tai thanh, va thanh, ha thanh
thanh vi » hanh vi, thanh va, thanh ve
su sach » so sach, vu sach
vu nang » vuc nang, va nang, vu dang
nang xa » nang x, lang xa, nang ma
ban tum » ban tu
cua tre » cua te, cuu tre, cua triet
tum ta » tum xa
vi cua » vai cua, di cua

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 (do sanh)) vu nang xa hoi. hieu van ban tum ta thanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (do sanh)) vu nang xa hoi. hieu van ban tum ta thanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (do sanh)) vu nang xa hoi. hieu van ban tum ta thanh vi cua tre*.