Perhaps you should try some spelling variations:
"so sach cha me gioi co thong minh" » "so sach cha me gioi co thong tin", "so sach cha me gioi co hoang minh", "so sach che me gioi co thong minh", "so sach ha me gioi co thong minh", "so sach cua me gioi co thong minh", "so sach cha me gioi bo thong minh", "so sach cha me gioi co trong minh", "so sach cha me gioi co phong minh", "so sanh cha me gioi co thong minh", "bo sach cha me gioi co thong minh", "co sach cha me gioi co thong minh", "so sach cha me giai co thong minh", "so sach cha me nguoi co thong minh", "so sach cha moi gioi co thong minh"
"so sach nha ve gioi co thong minh" » "so sach nha ve gioi co thong tin", "so sach nha ve gioi co hoang minh", "so sach nha ve gioi bo thong minh", "so sach nha ve gioi co trong minh", "so sach nha ve gioi co phong minh", "so sanh nha ve gioi co thong minh", "bo sach nha ve gioi co thong minh", "co sach nha ve gioi co thong minh", "so sach nha ve nguoi co thong minh", "so sach nha ve giai co thong minh", "so sach nha vien gioi co thong minh", "so sach nha van gioi co thong minh", "so sach nhat ve gioi co thong minh", "so sach nhan ve gioi co thong minh", "so sach nha va gioi co thong minh"

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("so sach cha me gioi co thong minh") or ("so sach nha ve gioi co thong minh"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("so sach cha me gioi co thong minh") OR ("so sach nha ve gioi co thong minh")).
• Removing quotes may allow a broader search: (( so sach cha me gioi co thong minh ) or ( so sach nha ve gioi co thong minh )).
• Adding a wildcard symbol may retrieve word variants: (("so sach cha me gioi co thong minh") or ("so sach nha ve gioi co thong minh"))*.