Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
ban hanh » ban hang
nang cau » nang cao, hang cau, nang dau
lam xuc » cam xuc, lam duoc
van lam » van nam
sach ky » sac ky, sach y, sach kem
sach ty » sach y, sach tu, sach thu
cua tre » cua te, cuu tre, cua triet
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: tu ((sach ky) OR (sach ty)) nang cau hoi. hieu van lam xuc ((ban hanh) or (van ban)) vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach ty)) nang cau hoi. hieu van lam xuc ((ban hanh) OR (van ban)) vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) OR (sach ty)) nang cau hoi. hieu van lam xuc ((ban hanh) or (van ban)) vi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) OR (sach ty)) nang cau hoi. hieu van lam xuc ((ban hanh) or (van ban)) vi cua tre*.