Perhaps you should try some spelling variations:
quoc bao » quoc oai, hoc bao, quoc va
hang tai » hang va, dung tai
hien cac » thien cac, vien cac, dien cac
bao hang » bao thang, ban hang, bao hanh
hieu cac » hieu luc, hieu va, hieu van
tu sach » thu sach, su sach, te sach
cao hoi » cau hoi, cao hoc, tao hoi
tai cua » thai cua, tai cuc, tri cua
sach ky » sac ky, sach y, sach ty
cua te » cua tu
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: tu sach ky nang ((cao hoi) or (co hoi)). hieu ((hien cac) OR (hieu cac)) quoc bao hang tai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ((cao hoi) OR (co hoi)). hieu ((hien cac) OR (hieu cac)) quoc bao hang tai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang ((cao hoi) or (co hoi)). hieu ((hien cac) OR (hieu cac)) quoc bao hang tai cua te".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ((cao hoi) or (co hoi)). hieu ((hien cac) OR (hieu cac)) quoc bao hang tai cua te*.