Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
hieu van » hieu va, thien van, lieu va
thanh va » thanh van, hanh va, thanh ha
tuc ban » thuc ban, truc ban, tu ban
cam tuc » cam xuc, cam tu, nam thuc
su tien » su kien, su hien, tu tieng
sach ky » sac ky, sach ty, sach kem
hieu ve » hieu va
x hoi » xa hoi, o hoi, x ho

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