Perhaps you should try some spelling variations:
tan vanh » tan van, tan vinh, tan thanh
vanh dai » van dai, vanh tai, lanh dao
va triet » va thiet, va trien, ve triet
su sach » so sach, vu sach
sach tu » sach thu, cach tu, sach ty
tu nang » tru nang, tu nong, tu nano
ve cham » va cham, ve chat, vu cham
va tham » van tham, va cham, va thanh
dai va » mai va
x hoi » xa hoi, o hoi, 5 hoi

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 tu nang ((x hoi) or (x ho)). hieu ((ve cham) or (va tham)) duc tan vanh dai va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach tu nang ((x hoi) OR (x ho)). hieu ((ve cham) OR (va tham)) duc tan vanh dai va triet.
• Adding a wildcard symbol may retrieve word variants: su sach tu nang ((x hoi) or (x ho)). hieu ((ve cham) or (va tham)) duc tan vanh dai va triet*.