Perhaps you should try some spelling variations:
cua triet » su triet, va triet
nang van » dang van, tang van, lang van
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
vat hanh » vat thanh, van hanh, va hanh
cua viet » ca viet, hoa viet, cua vat
van hoe » van hoa, van hoc, van hieu
su sac » su sach, su cac
su xac » pu xac, su cac

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sac) OR (su xac)) ky nang van hoe. hieu van nam thuc vat hanh vi ((cua triet) OR (cua viet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sac) or (su xac)) ky nang van hoe. hieu van nam thuc vat hanh vi ((cua triet) OR (cua viet))~".
• Adding a wildcard symbol may retrieve word variants: ((su sac) or (su xac)) ky nang van hoe. hieu van nam thuc vat hanh vi ((cua triet) OR (cua viet))*.