Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
cuc triet » cua triet, su triet, cac trieu
truc va » thuc va, trung va
han tai » hang tai, nhan tai, van tai
y nang » ky nang, ly nang, v nang
va cau » van cau, va cac, va dau
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.

• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach y nang ((x hoi) OR (o hoi)). lieu va cau ((truc va) OR (thuc vat)) han tai cuc triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach y nang ((x hoi) or (o hoi)). lieu va cau ((truc va) OR (thuc vat)) han tai cuc triet~".
• Adding a wildcard symbol may retrieve word variants: thuoc sach y nang ((x hoi) or (o hoi)). lieu va cau ((truc va) OR (thuc vat)) han tai cuc triet*.