Perhaps you should try some spelling variations:
"su quach nguyen thai" » "su quang nguyen thai", "su hoach nguyen thai", "su xuan nguyen thai", "su quach nguyen thi", "su quach nguyen hai", "su quach nguyen thanh", "su quan nguyen thai"
"so sach luan tri" » "so sach luyen tri", "so san luan tri", "so sach quan tri", "so sach luan thi", "so sach luat tri", "so sanh luan tri", "bo sach luan tri", "co sach luan tri"
"su sach han tai" » "su sach tham tai", "su sach danh tai", "su sach nang tai", "vu sach han tai", "su sach hang tai", "su sach nhan tai", "su sach van tai"

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (((("su sach han tai") OR ("so sach luan tri"))) OR ("su quach nguyen thai"))~.
• Removing quotes may allow a broader search: (((( su sach han tai ) or ( so sach luan tri ))) or ( su quach nguyen thai ))~.
• Adding a wildcard symbol may retrieve word variants: (((("su sach han tai") or ("so sach luan tri"))) or ("su quach nguyen thai"))*.