Perhaps you should try some spelling variations:
hieu hien » bieu hien, dieu hien, chieu chien
hien cac » thien cac, vien cac, hieu cac
tu sach » thu sach, te sach, tu cach
su sach » so sach, vu sach
cac tuc » cac toc, cac tu, cac tac
danh vi » dinh vi, danh di, danh va
luu tre » luu tru, cuu tre, luy tre
x hoi » xa hoi, o hoi, x ho

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) OR (su sach)) ky nang x hoi. hieu hien cac tuc xa ((danh vi) OR (hanh vi)) luu tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (su sach)) ky nang x hoi. hieu hien cac tuc xa ((danh vi) OR (hanh vi)) luu tre~".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) ky nang x hoi. hieu hien cac tuc xa ((danh vi) OR (hanh vi)) luu tre*.