Perhaps you should try some spelling variations:
tan thanh » tran thanh, tang thanh, toan thanh
sach thu » sach thue, sach thieu, sach tham
thu nang » thi nang, thu hang, thu bang
thanh vi » hanh vi, thanh va, thanh ve
cua viet » ca viet, hoa viet, cua vat
tu sach » thu sach, su sach, te sach
cao duc » dao duc, cao suc, giao duc
ma hoi » mai hoi, ma hoa, me hoi
va cao » va cac, va co, va dao
vi cua » vai cua, di cua

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 thu nang ((ma hoi) or (xa hoi)). lieu va cao duc tan thanh vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach thu nang ((ma hoi) OR (xa hoi)). lieu va cao duc tan thanh vi cua viet*.