Perhaps you should try some spelling variations:
thuc dan » thuc hanh, hoc dan
hanh vai » hanh vi, hanh va, hanh tai
va triet » va thiet, va trien, ve triet
vu sach » vu bach, su sach, vu khach
cao hoi » co hoi, cao hoc, tao hoi
hieu va » lieu va, hieu qua
y nang » ky nang, ly nang, v nang
va nam » van nam, ha nam, va nay
vai va » mai va, dai va, hai va

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 ((cao hoi) OR (cau hoi)). hieu va nam ((thuc dan) or (thuc vat)) hanh vai va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach y nang ((cao hoi) OR (cau hoi)). hieu va nam ((thuc dan) OR (thuc vat)) hanh vai va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach y nang ((cao hoi) OR (cau hoi)). hieu va nam ((thuc dan) or (thuc vat)) hanh vai va triet".
• Adding a wildcard symbol may retrieve word variants: vu sach y nang ((cao hoi) OR (cau hoi)). hieu va nam ((thuc dan) or (thuc vat)) hanh vai va triet*.