Perhaps you should try some spelling variations:
"so sanh thanh ky thuat xay hoc" » "so danh thanh ky thuat xay hoc", "so anh thanh ky thuat xay hoc", "so san thanh ky thuat xay hoc", "so sanh hanh ky thuat xay hoc", "so sanh thanh tay thuat xay hoc", "so sanh thanh huy thuat xay hoc", "do sanh thanh ky thuat xay hoc", "so sanh thanh ky thuat day hoc", "so sanh thanh ky thuat xa hoc"
"so sach than ky thuat toan hoc" » "so sach tham ky thuat toan hoc", "so sach han ky thuat toan hoc", "so sach tranh ky thuat toan hoc", "so sach than ky thuat toan khoa", "so sach than ky thuat van hoc", "so sach than ky thuat hoa hoc", "bo sach than ky thuat toan hoc", "co sach than ky thuat toan hoc", "hoc sach than ky 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 sanh thanh ky thuat xay hoc") or ("so sach than ky thuat toan hoc"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("so sanh thanh ky thuat xay hoc") OR ("so sach than ky thuat toan hoc"))*.
• Removing quotes may allow a broader search: (( so sanh thanh ky thuat xay hoc ) or ( so sach than ky thuat toan hoc ))*.