Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hanh hai » thanh hai, nhanh hai, hang hai
quoc bao » quoc oai, hoc bao, quoc va
quoc ban » quoc lan, quoc quan, quoc binh
hai cua » thai cua, dai cua, hoi cua
tu sach » thu sach, te sach, tu cach
hieu ve » hieu va, hieu van
su sach » so sach, vu sach
ve cam » ve cham, ve cac, va cam
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) or (su sach)) ky nang x hoi. hieu ve cam ((quoc ban) OR (quoc bao)) hanh hai cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) ky nang x hoi. hieu ve cam ((quoc ban) OR (quoc bao)) hanh hai cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (su sach)) ky nang x hoi. hieu ve cam ((quoc ban) OR (quoc bao)) hanh hai cua triet".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) ky nang x hoi. hieu ve cam ((quoc ban) OR (quoc bao)) hanh hai cua triet*.