Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, doanh tai
bang cau » hang cau, bang cac, nang cao
hieu van » hieu va, thien van, lieu va
va thanh » gia thanh, ban thanh, va tinh
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
ky bang » ky nang, ky dang, ke bang
hieu ve » hieu va
cuc tre » duc tre, cua tre, cuu tre
cam tu » cam thu, nam tu, dam tu

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 bang cau hoi. ((hieu ve) or (hieu van)) cam tu va thanh tai cuc tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky bang cau hoi. ((hieu ve) OR (hieu van)) cam tu va thanh tai cuc tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky bang cau hoi. ((hieu ve) or (hieu van)) cam tu va thanh tai cuc tre*.