Perhaps you should try some spelling variations:
hanh dai » hanh tai, hanh dao, vanh dai
hieu van » hieu va, thien van, lieu va
va triet » va trien, ve triet, cua triet
ca viet » va viet, co viet, hoa viet
va hanh » van hanh, va thanh, va danh
nang ro » nang co, nang ho, nang ra
thuc va » thuc vat, thuc dan, thuc day
sac ky » cac ky, sai ky
van am » van nam, van lam, van dam
ro hoi » co hoi, o hoi, mo hoi
tu sac » tu sach, tu cac, tu san

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: tu sac ky nang ro hoi. hieu van am thuc va hanh dai ((((va triet) OR (va thiet))) OR (ca viet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky nang ro hoi. hieu van am thuc va hanh dai ((((va triet) OR (va thiet))) or (ca viet))~".
• Adding a wildcard symbol may retrieve word variants: tu sac ky nang ro hoi. hieu van am thuc va hanh dai ((((va triet) OR (va thiet))) or (ca viet))*.