Perhaps you should try some spelling variations:
ban thanh » ban hang
ban hanh » ban hang
tai cuu » tai cuc, tai buu, tai cua
cuu tre » cua tre, cau tren, cau treo
cam cuc » cam xuc, cham cuu, pham cuc
sach ky » sac ky, sach ty, sach kem
hieu ve » hieu va, hieu van
cao hoc » co hoc, cho hoc, chat hoc
ve cam » ve cham, ve cac, va cam

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 cam cuc ((ban thanh) OR (ban hanh)) tai cuu 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 cam cuc ((ban thanh) OR (ban hanh)) tai cuu 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 cam cuc ((ban thanh) OR (ban hanh)) tai cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sach y)) nang cao hoc. hieu ve cam cuc ((ban thanh) OR (ban hanh)) tai cuu tre*.