Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van tham » van thanh, van tuan, van chat
tham duc » pham duc, tham du, than duc
tu sach » thu sach, te sach, tu cach
su sach » so sach, vu sach
ty nang » ky nang, ty xang, ty hang
va hanh » van hanh, va thanh, va danh
van cau » van dau, van hau, van chat
x hoi » xa hoi, o hoi, x ho

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: ((tu sach) OR (su sach)) ty nang x hoi. hieu van tham duc va hanh ((van cau) OR (tai cuc)) tren~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (su sach)) ty nang x hoi. hieu van tham duc va hanh ((van cau) or (tai cuc)) tren~".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (su sach)) ty nang x hoi. hieu van tham duc va hanh ((van cau) or (tai cuc)) tren*.