Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, doanh tai
ban thanh » ban hanh, ban hang
hieu van » thien van, lieu va
tu sach » thu sach, su sach, te sach
tai duc » tai cuc, mai duc, tai du
cuc ban » cua ban, cac ban, cuu ban
cam cuc » cam xuc, cham cuu, pham cuc
duc tre » duoc tren, duc tien
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
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 nang cao hoc. ((((hieu ve) OR (hieu va))) or (hieu van)) cam cuc ban thanh tai duc tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang cao hoc. ((((hieu ve) OR (hieu va))) OR (hieu van)) cam cuc ban thanh tai duc tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang cao hoc. ((((hieu ve) OR (hieu va))) or (hieu van)) cam cuc ban thanh tai duc tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang cao hoc. ((((hieu ve) OR (hieu va))) or (hieu van)) cam cuc ban thanh tai duc tre*.