Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
ca tren » cau tren, cu tren, la tren
va hanh » van hanh, va thanh, va danh
lam luc » lao luc, lam duoc
van lam » van nam
sach ky » sach y, sach ty, sach kem
lang xa » lang ha, dang xay, lang van
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
luc va » duc va, tuc va, loc va

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 ky) OR (sac ky)) lang xa hoi. hieu van lam luc va hanh vi ((ca tren) or (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ky) OR (sac ky)) lang xa hoi. hieu van lam luc va hanh vi ((ca tren) OR (cua tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach ky) OR (sac ky)) lang xa hoi. hieu van lam luc va hanh vi ((ca tren) or (cua tre))".
• Adding a wildcard symbol may retrieve word variants: te ((sach ky) OR (sac ky)) lang xa hoi. hieu van lam luc va hanh vi ((ca tren) or (cua tre))*.