Perhaps you should try some spelling variations:
hieu van » thien van, lieu va, hieu ve
thu sac » thu sach, thu san, thu xac
nang xa » lang xa, nang ma, mang xa
hieu va » lieu va, hieu qua
dao duc » giao duc, tao duoc
va hanh » van hanh, va thanh, va danh
hanh di » hanh vi, hanh de, hang di
sac ky » cac ky, sai ky
di cua » dai cua, doi cua, de cua
cua su » qua su

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sac ky ((nang xa) OR (nang x)) hoi. ((hieu va) or (hieu van)) dao duc va hanh di cua su~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sac ky ((nang xa) OR (nang x)) hoi. ((hieu va) OR (hieu van)) dao duc va hanh di cua su.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sac ky ((nang xa) OR (nang x)) hoi. ((hieu va) or (hieu van)) dao duc va hanh di cua su".
• Adding a wildcard symbol may retrieve word variants: thu sac ky ((nang xa) OR (nang x)) hoi. ((hieu va) or (hieu van)) dao duc va hanh di cua su*.