Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
cau tren » cu tren, dau tren, ca tren
thanh vi » hanh vi, thanh va, thanh ve
hieu van » hieu va, thien van, lieu va
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cuu tre, cua triet
cuc ban » cua ban, cac ban, cuu ban
su sach » so sach, vu sach
van cam » van nam, van lam, van cau
cong ha » cong hoa, dong ha, cong tac
nang xa » nang x, lang xa, nang ma
cam cuc » cam xuc, cham cuu, pham cuc

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

• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky ((nang xa) OR (cong ha)) hoi. hieu van cam cuc ban thanh vi ((cua tre) OR (cau tren))~.
• Adding a wildcard symbol may retrieve word variants: su sach ky ((nang xa) or (cong ha)) hoi. hieu van cam cuc ban thanh vi ((cua tre) or (cau tren))*.