Perhaps you should try some spelling variations:
ban thanh » ban hanh
nang cho » nang chon, ngang cho, nang cao
ban hang » ngan hang
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
cho hoc » co hoc, khoa hoc
hieu va » lieu va, hieu qua
tai cau » tai cao
tai cac » tai cuc
va cam » va cham, va cac, va cao

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 cho hoc. hieu va cam xuc ((ban thanh) or (ban hang)) ((tai cau) OR (tai cac)) tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang cho hoc. hieu va cam xuc ((ban thanh) OR (ban hang)) ((tai cau) OR (tai cac)) tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang cho hoc. hieu va cam xuc ((ban thanh) or (ban hang)) ((tai cau) OR (tai cac)) tren".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang cho hoc. hieu va cam xuc ((ban thanh) or (ban hang)) ((tai cau) OR (tai cac)) tren*.