Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
van thanh » van tuan
cau tren » cu tren, dau tren, ca tren
su sach » so sach, vu sach
te sach » toc sach
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu va, hieu van
ve pham » vi pham, v pham, ve phan
tai cau » tai cac, tai cao

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) or (te sach)) ky nang ma hoa. hieu ve pham duc ((van thanh) OR (ban thanh)) tai cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (te sach)) ky nang ma hoa. hieu ve pham duc ((van thanh) OR (ban thanh)) tai cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (te sach)) ky nang ma hoa. hieu ve pham duc ((van thanh) OR (ban thanh)) tai cau tren".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (te sach)) ky nang ma hoa. hieu ve pham duc ((van thanh) OR (ban thanh)) tai cau tren*.