Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
cua viet » ca viet, hoa viet, cua dieu
tu sach » thu sach, su sach, te sach
vu sach » vu bach, su sach, vu khach
nang xa » nang x, lang xa, nang ma
vien da » vien dai, hien dai
dan hai » doan hai, dang hai, dan khai
da lao » da bao, da lam, da lat
lao va » tao va, cao va, bao va
va dan » ca dan, va dao, va dau

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) or (vu sach)) ky nang xa hoi. hieu vien da lao va dan hai ((cua viet) or (cua vat))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (vu sach)) ky nang xa hoi. hieu vien da lao va dan hai ((cua viet) OR (cua vat)).
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (vu sach)) ky nang xa hoi. hieu vien da lao va dan hai ((cua viet) or (cua vat))*.