Perhaps you should try some spelling variations:
dan thanh » dang thanh, danh thanh, ban thanh
thanh vai » thanh hai, thanh van, thanh tai
thuc dan » thuc hanh, hoc dan, thuc vat
ky lang » ky dang, ky tang, tay lang
van cac » van hac, van bac, dan cac
van cau » van dau, van hau, van chat
vai cua » dai cua, hai cua, lai cua
cua tre » cua te, cuu tre, cua triet
su sac » su sach, su cac, su xac

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sac ((ky lang) or (ky nang)) xa hoi. thien ((van cac) OR (van cau)) thuc dan thanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sac ((ky lang) OR (ky nang)) xa hoi. thien ((van cac) OR (van cau)) thuc dan thanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sac ((ky lang) or (ky nang)) xa hoi. thien ((van cac) OR (van cau)) thuc dan thanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: su sac ((ky lang) or (ky nang)) xa hoi. thien ((van cac) OR (van cau)) thuc dan thanh vai cua tre*.