Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
hieu van » hieu va, thien van, lieu va
thanh va » thanh van, hanh va, thanh ha
lam duoc » nam duoc, luat duoc, lam thuoc
lam xuc » cam xuc
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
sach tu » sach thu, cach tu, sach ty
cua tre » cua te, cuu tre, cua triet
va cua » va chua, via cua, ca cua

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) or (sach tu)) nang xa hoi. hieu van ((lam xuc) OR (lam duoc)) ban thanh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach tu)) nang xa hoi. hieu van ((lam xuc) OR (lam duoc)) ban thanh va cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sach tu)) nang xa hoi. hieu van ((lam xuc) OR (lam duoc)) ban thanh va cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sach tu)) nang xa hoi. hieu van ((lam xuc) OR (lam duoc)) ban thanh va cua tre*.