Perhaps you should try some spelling variations:
sach thi » sach thu, sach tai, sach thieu
thi nang » thi cong, ki nang, thi hanh
van hanh » van thanh, ban hanh, van anh
va triet » va thiet, va trien, ve triet
su sach » so sach, vu sach
van cac » van hac, van bac, dan cac
van cau » van dau, van hau, van chat
duc van » duc va, duc tan, duc manh
x hoi » xa hoi, o hoi, 5 hoi
vi va » vi van, vai va, vu va

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 thi nang ((x hoi) OR (x ho)). hieu ((van cac) OR (van cau)) duc van hanh vi va triet~.
• Adding a wildcard symbol may retrieve word variants: su sach thi nang ((x hoi) or (x ho)). hieu ((van cac) or (van cau)) duc van hanh vi va triet*.