Perhaps you should try some spelling variations:
dieu hien » dieu khien, dieu kien, bieu hien
hieu viec » nhieu viec, hieu ve, sieu viet
hang di » hang doi, hang vi, hang dien
hanh di » hanh vi, hanh de, danh di
tu sach » thu sach, su sach, te sach
cuu tre » cua tre, cau tren, cau treo
sach ky » sac ky, sach y, sach ty
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.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky nang x hoi. ((hieu viec) or (dieu hien)) cac tu va ((hanh di) OR (hang di)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang x hoi. ((hieu viec) OR (dieu hien)) cac tu va ((hanh di) OR (hang di)) cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang x hoi. ((hieu viec) or (dieu hien)) cac tu va ((hanh di) OR (hang di)) cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang x hoi. ((hieu viec) or (dieu hien)) cac tu va ((hanh di) OR (hang di)) cuu tre*.