Perhaps you should try some spelling variations:
"su sach nganh ky thuat toan khoa" » "su sach ngan ky thuat toan khoa", "su sach tranh ky thuat toan khoa", "su cac nganh ky thuat toan khoa", "su sach nganh y thuat toan khoa", "su sach hanh ky thuat toan khoa", "su sach nganh co thuat toan khoa", "so sach nganh ky thuat toan khoa", "vu sach nganh ky thuat toan khoa"
"co sach nganh xay thuat toan hoc" » "co sach ngan xay thuat toan hoc", "co sach tranh xay thuat toan hoc", "co cac nganh xay thuat toan hoc", "co sach nganh mac thuat toan hoc", "co sach nganh y thuat toan hoc", "co sach nganh ma thuat toan hoc", "co sach nganh my thuat toan hoc", "co sach nganh va thuat toan hoc", "co sach nganh cac thuat toan hoc", "co sach nganh xay thuat van hoc", "co sach nganh xay thuat hoa hoc", "co sach nganh xay thuat tin hoc", "bo sach nganh xay thuat toan hoc", "cuon sach nganh xay thuat toan hoc", "hoc sach nganh xay thuat toan hoc"

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