Perhaps you should try some spelling variations:
nuoc ban » nuoc san, quoc ban, buoc ban
chua tre » chua tri, chua trieu, cho tre
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
ban anh » ban hanh, ban banh, ban danh
anh vua » anh va, anh cua, anh vu
cua tre » cua te, cuu tre, cua triet
ve hoc » te hoc, va hoc, vi hoc

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) or (cac ky)) nang x ho. hieu ve hoc nuoc ban anh vua ((chua tre) OR (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (cac ky)) nang x ho. hieu ve hoc nuoc ban anh vua ((chua tre) OR (cua tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (cac ky)) nang x ho. hieu ve hoc nuoc ban anh vua ((chua tre) OR (cua tre))".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (cac ky)) nang x ho. hieu ve hoc nuoc ban anh vua ((chua tre) OR (cua tre))*.