Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
kem phat » te phat, de phat, tam phat
sach va » sach xa, sach ha, sach dao
nang co » nang doc, nang noi, nang hoc
van lam » van nam
lam duc » lam duoc, pham duc, nam duoc
va hanh » van hanh, va thanh, va danh
sach v » sach y, sach 2, sach vay

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

• Performing a fuzzy search may retrieve terms with similar spellings: te ((sach v) or (sach va)) ((nang co) OR (nang cao)) hoi. hieu van lam duc va hanh kem phat trien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach v) OR (sach va)) ((nang co) OR (nang cao)) hoi. hieu van lam duc va hanh kem phat trien.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach v) or (sach va)) ((nang co) OR (nang cao)) hoi. hieu van lam duc va hanh kem phat trien".
• Adding a wildcard symbol may retrieve word variants: te ((sach v) or (sach va)) ((nang co) OR (nang cao)) hoi. hieu van lam duc va hanh kem phat trien*.