Perhaps you should try some spelling variations:
cua triet » cua viet, va triet
thuc van » thuc vat, thuc dan, thuc va
van hanh » van thanh, ban hanh, van anh
su triet » su viet, su tien, ve triet
vu sach » vu bach, su sach, vu khach
hieu ve » hieu van
hieu va » lieu va, hieu qua
y nang » ky nang, ly nang, v nang
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach y nang x hoi. ((hieu ve) or (hieu va)) am thuc van hanh vi ((cua triet) OR (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach y nang x hoi. ((hieu ve) OR (hieu va)) am thuc van hanh vi ((cua triet) OR (su triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach y nang x hoi. ((hieu ve) or (hieu va)) am thuc van hanh vi ((cua triet) OR (su triet))".
• Adding a wildcard symbol may retrieve word variants: vu sach y nang x hoi. ((hieu ve) or (hieu va)) am thuc van hanh vi ((cua triet) OR (su triet))*.