Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
vien cac » vien bach, vien dai, vien da
danh vai » danh sai, danh va, doanh van
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
cua tre » cuu tre, cua triet, dua tren
sach ky » sac ky, sach y, sach ty
cua te » cua tu
do va » do van, so va
bo va » bao va, so va, co va

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 ky nang xa hoi. hieu vien cac ((bo va) or (do va)) danh vai ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xa hoi. hieu vien cac ((bo va) OR (do va)) danh vai ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang xa hoi. hieu vien cac ((bo va) or (do va)) danh vai ((cua tre) OR (cua te))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. hieu vien cac ((bo va) or (do va)) danh vai ((cua tre) OR (cua te))*.