Perhaps you should try some spelling variations:
so sach » so sanh, bo sach, co sach
ky lang » ky nang, ky dang, ky tang
van hoi » van hoa, van hoe, van loi
van hoc » van hoa
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
va nam » van nam, ha nam, va nay
thu va » thuc va, thue va, tu va
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu cac) or (so sach)) ky lang ((van hoi) OR (van hoc)). lieu va nam thu va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cac) OR (so sach)) ky lang ((van hoi) OR (van hoc)). lieu va nam thu va hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu cac) or (so sach)) ky lang ((van hoi) OR (van hoc)). lieu va nam thu va hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu cac) or (so sach)) ky lang ((van hoi) OR (van hoc)). lieu va nam thu va hanh vi cua tre*.