Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
van thanh » van tuan
nang mai » nang ma, nang tai, lang mai
cac vuc » cac nuoc, cac vung, cac cuoc
tu sach » thu sach, su sach, tu cach
hieu va » lieu va, hieu qua
mai hoi » mai khoi, dai hoi, lai hoi
vu nang » vuc nang, va nang, vu dang
te sach » toc sach
su tien » su kien, su hien, tu tieng

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) or (te sach)) vu nang mai hoi. hieu va cac vuc ((van thanh) OR (ban thanh)) ky su tien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (te sach)) vu nang mai hoi. hieu va cac vuc ((van thanh) OR (ban thanh)) ky su tien.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (te sach)) vu nang mai hoi. hieu va cac vuc ((van thanh) OR (ban thanh)) ky su tien".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (te sach)) vu nang mai hoi. hieu va cac vuc ((van thanh) OR (ban thanh)) ky su tien*.