Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
dai luan » bai luan, dan luan, dat luan
dinh hai » dinh thai, tinh hai, dinh ha
te sach » toc sach
hai cua » thai cua, dai cua, hoi cua
va dinh » van dinh, va kinh, va tinh
dai lao » dai lan, dai thao, chai lao
nang xa » lang xa, nang ma, mang xa
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) or (nang x)) hoi. hieu vien ((dai lao) OR (dai luan)) va dinh hai cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y ((nang xa) OR (nang x)) hoi. hieu vien ((dai lao) OR (dai luan)) va dinh hai cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y ((nang xa) or (nang x)) hoi. hieu vien ((dai lao) OR (dai luan)) va dinh hai cua tu".
• Adding a wildcard symbol may retrieve word variants: te sach y ((nang xa) or (nang x)) hoi. hieu vien ((dai lao) OR (dai luan)) va dinh hai cua tu*.