Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, doanh tai
ban thanh » ban hanh, ban hang
hieu van » hieu va, thien van, lieu va
cac ban » cac dan, cac van, can ban
cam cac » ca cac, nam cac, cam chan
cuc tre » duc tre, cua tre, cuu tre
sach ky » sac ky, sach ty, sach kem
hieu ve » hieu va
cao hoc » co hoc, cho hoc, chat 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 (sach y)) nang cao hoc. ((hieu ve) OR (hieu van)) cam cac ban thanh tai cuc tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach y)) nang cao hoc. ((hieu ve) OR (hieu van)) cam cac ban thanh tai cuc tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sach y)) nang cao hoc. ((hieu ve) OR (hieu van)) cam cac ban thanh tai cuc tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sach y)) nang cao hoc. ((hieu ve) OR (hieu van)) cam cac ban thanh tai cuc tre*.