Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
cuu tre » cau tren, cau treo
va hanh » van hanh, va thanh, va danh
cam luc » cam xuc, cau luc
van cam » van nam, van lam, van cau
sach ky » sac ky, sach y, sach ty
tu sach » thu sach, su sach, te sach
tang ma » mang may, tang van
tang xa » trang xa, lang xa, tang ha
cua tre » cua te, cua triet, dua tren
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: tu sach ky ((tang xa) OR (tang ma)) hoi. hieu van cam luc va hanh vi ((cuu tre) or (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((tang xa) OR (tang ma)) hoi. hieu van cam luc va hanh vi ((cuu tre) OR (cua tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky ((tang xa) OR (tang ma)) hoi. hieu van cam luc va hanh vi ((cuu tre) or (cua tre))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((tang xa) OR (tang ma)) hoi. hieu van cam luc va hanh vi ((cuu tre) or (cua tre))*.