Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
vien cac » vien bach, vien dai, vien da
van hanh » van thanh, ban hanh, van anh
hanh vai » hanh vi, hanh va, hanh tai
sach ky » sac ky, sach ty, sach kem
lang xa » lang ha, dang xay, lang van
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: su ((sach ky) OR (sach y)) lang xa hoi. hieu vien cac vi van hanh vai ((cua te) or (cua tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (sach y)) lang xa hoi. hieu vien cac vi van hanh vai ((cua te) OR (cua tu)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ky) OR (sach y)) lang xa hoi. hieu vien cac vi van hanh vai ((cua te) or (cua tu))".
• Adding a wildcard symbol may retrieve word variants: su ((sach ky) OR (sach y)) lang xa hoi. hieu vien cac vi van hanh vai ((cua te) or (cua tu))*.