Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
vien cac » vien bach, vien dai, vien da
cac truc » cau truc, cac tru, cac trung
nang xa » nang x, lang xa, nang ma
truc va » thuc va, thuc vat, trung va
va hanh » van hanh, va thanh, va danh
sac ky » cac ky
vi cua » vai cua
di cua » dai cua, doi cua, de cua

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

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