Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
ca trung » cua trung, cac trung, cao trung
trung va » truong va, trang va, trung ha
cua tre » cua te, cuu tre, dua tren
danh ca » dan ca, doanh cua, danh cho
va danh » va dinh, va dan, va hanh
te sach » toc sach
hieu va » lieu va, hieu qua
y nang » ky nang, ly nang, v nang
me hoi » le hoi
va ca » va cac, va cao, va cai

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach y nang ((me hoi) or (ma hoa)). hieu va ca trung va danh ca ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y nang ((me hoi) OR (ma hoa)). hieu va ca trung va danh ca ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y nang ((me hoi) or (ma hoa)). hieu va ca trung va danh ca ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: te sach y nang ((me hoi) or (ma hoa)). hieu va ca trung va danh ca ((cua tre) OR (cua triet))*.