Perhaps you should try some spelling variations:
"su sach xa le giao cong thong minh" » "su sach xa le giao cong thuong minh", "su sach xa le giao cong trong minh", "su sach xa le giao dong thong minh", "su sach xa le giao cong hoang minh", "su sach xa le gia cong thong minh", "su sach xa le giao thong thong minh", "su sach xa le cao cong thong minh", "so sach xa le giao cong thong minh", "vu sach xa le giao cong thong minh", "su sach dao le giao cong thong minh", "su sach nha le giao cong thong minh", "su sach bai le giao cong thong minh", "su sach xa te giao cong thong minh", "su sach xa ve giao cong thong minh", "su sach xa ke giao cong thong minh", "su sach va le giao cong thong minh", "su sach ha le giao cong thong minh", "su sach xa la giao cong thong minh"
"thu bach ha de giai toan thong tin" » "thu bach ha de giai doan thong tin", "thu bach ha de giai toa thong tin", "thu bach ha de gioi toan thong tin", "thi bach ha de giai toan thong tin", "thu sach ha de giai toan thong tin", "thu hoach ha de giai toan thong tin", "thu bac ha de giai toan thong tin", "thu bich ha de giai toan thong tin", "thu bach ha dan giai toan thong tin", "thu bach ha kem giai toan thong tin", "thu bach hac de giai toan thong tin", "thu bach hat de giai toan thong tin", "thu bach va de giai toan thong tin"

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: (("thu bach ha de giai toan thong tin") or ("su sach xa le giao cong thong minh"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("thu bach ha de giai toan thong tin") OR ("su sach xa le giao cong thong minh")).
• Removing quotes may allow a broader search: (( thu bach ha de giai toan thong tin ) or ( su sach xa le giao cong thong minh )).
• Adding a wildcard symbol may retrieve word variants: (("thu bach ha de giai toan thong tin") or ("su sach xa le giao cong thong minh"))*.