Perhaps you should try some spelling variations:
"tu sach than ky thuat do hoc" » "tu sach tham ky thuat do hoc", "tu sach han ky thuat do hoc", "tu sach tranh ky thuat do hoc", "tu sach than ky thuat o hoc", "su sach than ky thuat do hoc", "te sach than ky thuat do hoc", "tu cach than ky thuat do hoc", "tu sach than ky thuat co hoc", "tu sach than ky thuat do hoa", "tu sach than ky thuat du hoc"
"thu sach dung ky thuat toan hoc" » "thuat sach dung ky thuat toan hoc", "thuoc sach dung ky thuat toan hoc", "thu hoach dung ky thuat toan hoc", "thu sach dung ky thuat toan khoa", "thu sach dung ky thuat van hoc", "thu sach dung ky thuat hoa hoc", "thu sach mung ky thuat toan hoc", "thu sach vung ky thuat toan hoc", "thu sach dung may 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: (("tu sach than ky thuat do hoc") or ("thu sach dung ky thuat toan hoc"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("tu sach than ky thuat do hoc") OR ("thu sach dung ky thuat toan hoc")).
• Removing quotes may allow a broader search: (( tu sach than ky thuat do hoc ) or ( thu sach dung ky thuat toan hoc )).
• Adding a wildcard symbol may retrieve word variants: (("tu sach than ky thuat do hoc") or ("thu sach dung ky thuat toan hoc"))*.