Perhaps you should try some spelling variations:
"so sach ngan ky thuat toan khoa" » "so sach ngon ky thuat toan khoa", "so sach nha ky thuat toan khoa", "so sach han ky thuat toan khoa", "so sanh ngan ky thuat toan khoa", "bo sach ngan ky thuat toan khoa", "co sach ngan ky thuat toan khoa", "so sach nganh ky thuat toan khoa", "so sach nhan ky thuat toan khoa", "so sach ngan hay thuat toan khoa"
"so sach hanh ma thuat toan hoc" » "so sach danh ma thuat toan hoc", "so sach han ma thuat toan hoc", "so sac hanh ma thuat toan hoc", "so sach hanh my thuat toan hoc", "so sach hanh va thuat toan hoc", "so sach hanh mi thuat toan hoc", "so sach hanh ma thuat van hoc", "so sach hanh ma thuat hoa hoc", "so sach hanh ma thuat tin hoc", "so sanh hanh ma thuat toan hoc", "bo sach hanh ma thuat toan hoc", "co sach hanh ma thuat toan hoc", "so sach hanh mau thuat toan hoc", "so sach hanh may thuat toan hoc"

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 ngan ky thuat toan khoa") or ("so sach hanh ma thuat toan hoc"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("so sach ngan ky thuat toan khoa") OR ("so sach hanh ma thuat toan hoc")).
• Removing quotes may allow a broader search: (( so sach ngan ky thuat toan khoa ) or ( so sach hanh ma thuat toan hoc )).
• Adding a wildcard symbol may retrieve word variants: (("so sach ngan ky thuat toan khoa") or ("so sach hanh ma thuat toan hoc"))*.