Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
vien cac » vien bach, vien dai, vien da
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
cac luc » cau luc, coc luc, cac nuoc
va hanh » van hanh, va thanh, va danh
bai cua » ban cua, bai ca, hai cua
luc va » duc va, tuc va, loc va

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 ((nang xa) OR (lang xa)) hoi. hieu vien cac luc va hanh ((bai cua) or (dai cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu cac ky ((nang xa) OR (lang xa)) hoi. hieu vien cac luc va hanh ((bai cua) OR (dai cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cac ky ((nang xa) OR (lang xa)) hoi. hieu vien cac luc va hanh ((bai cua) or (dai cua)) triet".
• Adding a wildcard symbol may retrieve word variants: tu cac ky ((nang xa) OR (lang xa)) hoi. hieu vien cac luc va hanh ((bai cua) or (dai cua)) triet*.