Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh vi » hanh vi, thanh va, thanh ve
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
cua tre » cua te, cua triet, dua tren
duc ban » duc tan, duc van, dua ban
van dau » van dao, phan dau
van cau » van hau, van chat, toan cau
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
cuu tre » cau tren, cau treo

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 ty nang xa hoi. hieu ((van cau) OR (van dau)) duc ban thanh vi ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty nang xa hoi. hieu ((van cau) OR (van dau)) duc ban thanh vi ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty nang xa hoi. hieu ((van cau) OR (van dau)) duc ban thanh vi ((cua tre) or (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: su sach ty nang xa hoi. hieu ((van cau) OR (van dau)) duc ban thanh vi ((cua tre) or (cuu tre))*.