Perhaps you should try some spelling variations:
cua triet » cua viet, su triet
thu sach » thuat sach, thuoc sach, thu hoach
van hanh » van thanh, ban hanh, van anh
hieu van » hieu va, thien van, lieu va
va triet » va thiet, va trien, ve triet
tang xa » trang xa, tang ma, lang xa
ky tang » ky nang, ky dang, kho tang
cau luc » cau truc, cau phuc
luc van » luoc van, luu van, duc van
tu sach » su sach, te sach, tu cach
hanh de » hanh ve, hanh kem
van cau » van dau, van hau, van chat

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((thu sach) or (tu sach)) ky tang xa hoi. hieu van cau luc van hanh de ((cua triet) OR (va triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (tu sach)) ky tang xa hoi. hieu van cau luc van hanh de ((cua triet) OR (va triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) or (tu sach)) ky tang xa hoi. hieu van cau luc van hanh de ((cua triet) OR (va triet))".
• Adding a wildcard symbol may retrieve word variants: ((thu sach) or (tu sach)) ky tang xa hoi. hieu van cau luc van hanh de ((cua triet) OR (va triet))*.