Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
hang vi » hang va, hanh vi, khang voi
hang di » hang doi, hang dien, hang dich
so sach » so sanh, bo sach, co sach
cac tuc » cac toc, cac tac, cac nuoc
hieu va » lieu va, hieu qua
y nang » ky nang, ly nang, v nang
cac tu » cac thu, cach tu, cac du
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: so sach y nang x hoi. hieu va ((cac tuc) OR (cac tu)) van ((hang di) OR (hang vi)) cua viet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach y nang x hoi. hieu va ((cac tuc) OR (cac tu)) van ((hang di) or (hang vi)) cua viet~".
• Adding a wildcard symbol may retrieve word variants: so sach y nang x hoi. hieu va ((cac tuc) OR (cac tu)) van ((hang di) or (hang vi)) cua viet*.