Perhaps you should try some spelling variations:
thanh dat » thanh san, thanh hai, thanh van
toc sach » hoc sach, doc sach, thuoc sach
va thanh » gia thanh, ban thanh, va tinh
dat cua » dai cua, day cua, mat cua
van hac » van hoc, van ha, van hai
van cac » van cau, van bac, dan cac
mai hoi » mai khoi, dai hoi, lai hoi
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
ma hoi » xa hoi, ma hoa, me hoi
du va » dau va, tu va, su va

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: toc sach y nang ((ma hoi) OR (mai hoi)). hieu ((van cac) OR (van hac)) du va thanh dat cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach y nang ((ma hoi) or (mai hoi)). hieu ((van cac) OR (van hac)) du va thanh dat cua tre~".
• Adding a wildcard symbol may retrieve word variants: toc sach y nang ((ma hoi) or (mai hoi)). hieu ((van cac) OR (van hac)) du va thanh dat cua tre*.