Perhaps you should try some spelling variations:
va thieu » va thiet, va hieu, va tieu
va triet » va thiet, va trien, ve triet
nam thuc » nam thuoc, am thuc, nam thu
cao hoi » cau hoi, co hoi, cao hoc
hieu ve » hieu va, hieu van
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
hanh va » hang va, hanh vi
ly nang » ly hang, ly vang, ly quang
su sach » so sach, vu sach
ve nam » he nam, va nam, le nam

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

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