Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
vien canh » bien canh, vien can, vien nganh
canh thuc » anh thuc, cach thuc, danh thuc
vat tinh » sat tinh, vat sinh, hoat tinh
cay phoi » cap phoi, tay hoi, cay cho
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
xay hoi » xa hoi, tay hoi, gay thoi
va chu » va cau, va chi

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 ((xay hoi) or (cay phoi)). hieu vien canh thuc vat tinh ((va chu) OR (va che)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ((xay hoi) OR (cay phoi)). hieu vien canh thuc vat tinh ((va chu) OR (va che)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang ((xay hoi) or (cay phoi)). hieu vien canh thuc vat tinh ((va chu) OR (va che)) tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ((xay hoi) or (cay phoi)). hieu vien canh thuc vat tinh ((va chu) OR (va che)) tre*.