Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
thanh van » thanh san, thanh toan, thanh phan
va thanh » gia thanh, ban thanh, va tinh
van cua » vang cua, ban cua, dan cua
sach ty » sach y, sach tu, sach thu
tu sach » thu sach, su sach, te sach
ty nang » ky nang, ty xang, ty hang
luc va » duc va, tuc va, loc va
va cao » va cac, va co, va dao
va cam » va cham, va cac, va cai
o hai » co hai, so hai, o lai
o hoi » co hoi, o hoc, o hoa

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