Perhaps you should try some spelling variations:
hieu hien » bieu hien, dieu hien, chieu chien
cau tren » cu tren, dau tren, ca tren
hang tai » hang va, dung tai
ban hang » ngan hang
quoc ban » quoc bao, quoc lan, quoc quan
hien cac » thien cac, vien cac, hieu cac
cac quoc » cac nuoc, cac cuoc, cao quoc
sach ky » sac ky, sach y, sach ty
cao hoi » cau hoi, cao hoc, tao hoi
cuu tre » cua tre, cau treo
te sach » toc sach
co hoi » co hoc, co loi

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

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