Perhaps you should try some spelling variations:
hieu hien » bieu hien, dieu hien, chieu chien
cua viet » ca viet, cua vat, cua dieu
hien cac » thien cac, vien cac, hieu cac
dinh vai » dinh van, dinh vi, dinh va
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
sach ky » sac ky, sach y, sach ty
bao va » bao ve, tao va, ban va
do van » dao van, vo van, so van

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

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