Perhaps you should try some spelling variations:
cach thuc » anh thuc, cac thu
sach thue » sach thu, sach thieu, sach tham
cac thuc » cac thu, can thuc, cay thuc
van hanh » van thanh, ban hanh, van anh
sach ty » sach y, sach tu, sach thu
cua tre » cua te, cuu tre, cua triet
ang xa » lang xa, mang xa, dang xay
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: su ((sach ty) or (sach thue)) ang xa hoi. lieu va ((cac thuc) OR (cach thuc)) van hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ty) OR (sach thue)) ang xa hoi. lieu va ((cac thuc) OR (cach thuc)) van hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ty) or (sach thue)) ang xa hoi. lieu va ((cac thuc) OR (cach thuc)) van hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) or (sach thue)) ang xa hoi. lieu va ((cac thuc) OR (cach thuc)) van hanh vi cua tre*.