Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
ban hanh » ban hang
van lam » van nam
vai cua » dai cua, hai cua, lai cua
lam xuc » cam xuc, lam duoc
cua tre » cua te, cuu tre, cua triet
nang ma » tang ma, nang cao, mang may
sang ma » tang ma, sang tao, mang may
sac ky » cac ky, sai ky
tu sac » tu sach, tu cac, tu san

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky ((nang ma) or (sang ma)) hoi. hieu van lam xuc ((ban hanh) or (van ban)) vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky ((nang ma) OR (sang ma)) hoi. hieu van lam xuc ((ban hanh) OR (van ban)) vai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sac ky ((nang ma) or (sang ma)) hoi. hieu van lam xuc ((ban hanh) or (van ban)) vai cua tre*.