Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
ban thanh » ban hanh, ban hang
cua triet » cua viet, su triet, va triet
tu sach » thu sach, su sach, te sach
van cac » van hac, van cau, dan cac
van bac » van ban, van bao, van hac
dac ban » cac ban, dac san, duc ban
y nang » ky nang, ly nang, v nang
x hoi » xa hoi, x ho, 5 hoi
o hoi » co hoi, o hoc, o hai

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 y nang ((x hoi) or (o hoi)). hieu ((van cac) OR (van bac)) dac ban thanh dai cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang ((x hoi) OR (o hoi)). hieu ((van cac) OR (van bac)) dac ban thanh dai cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang ((x hoi) or (o hoi)). hieu ((van cac) OR (van bac)) dac ban thanh dai cua triet".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang ((x hoi) or (o hoi)). hieu ((van cac) OR (van bac)) dac ban thanh dai cua triet*.