Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
hanh lai » hanh lam, hanh tai, thanh lap
van hanh » van thanh, ban hanh, van anh
lai cua » dai cua, hai cua, lai chau
nang xa » nang x, lang xa, mang xa
vien da » vien dai, hien dai
nang ma » tang ma, sang ma, nang cao
sach ky » sac ky, sach y, sach ty
sai ky » sac ky
cua te » cua tu
da vo » da voi, dat vo, va vo

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

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