Perhaps you should try some spelling variations:
kho tang » cao tang
hanh vai » hanh vi, hanh va, hanh tai
hieu van » hieu va, thien van, lieu va
ky tang » ky nang, ky dang, ky trong
va hanh » van hanh, va thanh, va danh
vai cuu » vai cua
hao duc » dao duc, cao duc, ha duc
lai hoi » dai hoi, lai hoa, lai roi
cuu tre » cua tre, cau tren, cau treo
ho duc » hoc duc, do duc, hong duc

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu cac ((ky tang) or (kho tang)) lai hoi. hieu van ((hao duc) OR (ho duc)) va hanh vai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu cac ((ky tang) OR (kho tang)) lai hoi. hieu van ((hao duc) OR (ho duc)) va hanh vai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cac ((ky tang) or (kho tang)) lai hoi. hieu van ((hao duc) OR (ho duc)) va hanh vai cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu cac ((ky tang) or (kho tang)) lai hoi. hieu van ((hao duc) OR (ho duc)) va hanh vai cuu tre*.