Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
cau treo » cau theo, cau tren, cau triet
danh vai » danh sai, danh va, doanh van
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
cac toc » cac toi, cac thoi
sach ky » sac ky, sach y, sach ty
ta danh » tac danh, tao danh, tap danh
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet
te sach » toc sach

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky nang xa hoi. hieu vien ((cac toc) OR (cac nuoc)) ta danh vai ((cua tre) or (cau treo))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang xa hoi. hieu vien ((cac toc) OR (cac nuoc)) ta danh vai ((cua tre) OR (cau treo)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang xa hoi. hieu vien ((cac toc) OR (cac nuoc)) ta danh vai ((cua tre) or (cau treo))".
• Adding a wildcard symbol may retrieve word variants: te sach ky nang xa hoi. hieu vien ((cac toc) OR (cac nuoc)) ta danh vai ((cua tre) or (cau treo))*.