Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
nhan luc » nang luc
dang van » hoang van, hang va
tu sach » thu sach, su sach, te sach
vai cua » dai cua, hai cua, lai cua
va nhan » van nhan, ca nhan, va phan
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
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: tu sach ky ((dang van) or (nang x)) hoi. hieu va nhan luc ((ban thanh) or (gia thanh)) vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((dang van) OR (nang x)) hoi. hieu va nhan luc ((ban thanh) OR (gia thanh)) vai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((dang van) or (nang x)) hoi. hieu va nhan luc ((ban thanh) or (gia thanh)) vai cua tre*.