Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
doanh van » doan van, doanh ban, doanh nhan
vien cac » vien bach, vien dai, vien da
doanh va » doan va, doanh tai, doanh cua
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
cuu tre » cua tre, cau tren, cau treo
y nang » ky nang, ly nang, v nang
lo van » vo van, so van, do van

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach y nang xa hoi. hieu vien cac ((lo van) or (le van)) ((doanh van) OR (doanh va)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang xa hoi. hieu vien cac ((lo van) OR (le van)) ((doanh van) OR (doanh va)) cuu tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang xa hoi. hieu vien cac ((lo van) or (le van)) ((doanh van) OR (doanh va)) cuu tre*".