Perhaps you should try some spelling variations:
cua triet » su triet, va triet
cua viet » ca viet, hoa viet, cua vat
cac thuc » cach thuc, cac thu, can thuc
hieu van » hieu va, thien van, lieu va
hang ca » hang va, nang cao, hang tai
van cac » van hac, van cau, van bac
so sanh » do sanh
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
bo sach » co sach, hoc sach
y hang » ly hang, ty hang, yu hang
ca hoi » cau hoi, cua hoi, xa hoi

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

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