Perhaps you should try some spelling variations:
hieu viec » nhieu viec, hieu ve, sieu viet
hieu vien » hieu hien, thieu nien, hieu tieng
sach ky » sac ky, sach y, sach ty
tu sach » thu sach, su sach, te sach
cua tre » cua te, cuu tre, cua triet
bac tu » ban tu, tac tu, cac tu
ca dan » ca dao
vi cua » vai cua, di cua
x hoi » xa hoi, o hoi, x ho

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 x hoi. ((hieu vien) OR (hieu viec)) bac tu ((ca dan) or (cac dan)) vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang x hoi. ((hieu vien) OR (hieu viec)) bac tu ((ca dan) OR (cac dan)) vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang x hoi. ((hieu vien) OR (hieu viec)) bac tu ((ca dan) or (cac dan)) vi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang x hoi. ((hieu vien) OR (hieu viec)) bac tu ((ca dan) or (cac dan)) vi cua tre*.