Perhaps you should try some spelling variations:
"so dinh hanh ky thuat bai hoc" » "so dinh thanh ky thuat bai hoc", "so dinh khanh ky thuat bai hoc", "so dinh hoang ky thuat bai hoc", "so dinh hanh ky thuat bao hoc", "so dinh hanh ky thuyet bai hoc", "so dinh hanh ky thuat xay hoc", "do dinh hanh ky thuat bai hoc", "co dinh hanh ky thuat bai hoc", "so sinh hanh ky thuat bai hoc", "so dinh hanh kem thuat bai hoc", "so dinh hanh ky thuat dai hoc"
"so sach nhan ky thuat toan khoa" » "so sach nha ky thuat toan khoa", "so sach han ky thuat toan khoa", "so sach ngan ky thuat toan khoa", "so sanh nhan ky thuat toan khoa", "bo sach nhan ky thuat toan khoa", "co sach nhan ky thuat toan khoa", "so sach nhan y thuat toan khoa", "so sach nhat ky thuat toan khoa", "so sach than ky thuat toan khoa", "so sach nhan ky thuat tran khoa"

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

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