Perhaps you should try some spelling variations:
hieu vien » hieu viec, thieu nien, hieu tieng
hieu hien » bieu hien, dieu hien, chieu chien
dinh vai » dinh van, dinh vi, dinh va
te sach » toc sach
nang xa » nang x, lang xa, nang ma
luan va » luat va
vai cua » dai cua, hai cua, lai cua
y nang » ky nang, ly nang, v nang
cua tu » cua tuc, cua su, cua cu

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 xa hoi. ((hieu vien) or (hieu hien)) bai ((luan va) OR (luan van)) dinh vai cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y nang xa hoi. ((hieu vien) OR (hieu hien)) bai ((luan va) OR (luan van)) dinh vai cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y nang xa hoi. ((hieu vien) or (hieu hien)) bai ((luan va) OR (luan van)) dinh vai cua tu".
• Adding a wildcard symbol may retrieve word variants: te sach y nang xa hoi. ((hieu vien) or (hieu hien)) bai ((luan va) OR (luan van)) dinh vai cua tu*.