Perhaps you should try some spelling variations:
"tu can trinh kxy thuat san hoc" » "tu can tranh kxy thuat san hoc", "tu dan trinh kxy thuat san hoc", "tu van trinh kxy thuat san hoc", "tu can trinh ky thuat san hoc", "tu can trinh ly thuat san hoc", "tu can trinh ke thuat san hoc", "tu can trinh ki thuat san hoc", "tu can trinh my thuat san hoc", "tu can trinh ky thua san hoc", "tu can trinh kxy thuat toan hoc", "tu can trinh kxy thuat song hoc", "tu can trinh kxy thuat lanh hoc", "tu can trinh kxy thuat van hoc", "tu can trinh kxy thuat dan hoc", "tu can trinh kxy thuat san ho", "tu ban trinh kxy thuat san hoc", "tu cac trinh kxy thuat san hoc", "thu canh trinh kxy thuat san hoc"
"te sach han ky thuat do hoc" » "te sach tham ky thuat do hoc", "te sach danh ky thuat do hoc", "te sach nang ky thuat do hoc", "te sach han ky thuat o hoc", "toc sach han ky thuat do hoc", "te sach hanh ky thuat do hoc", "te sach than ky thuat do hoc", "te sach nhan ky thuat do hoc", "te sach han ky thuat co hoc", "te sach han ky thuat do hoa", "te sach han ky thuat du 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: (("te sach han ky thuat do hoc") or ("tu can trinh kxy thuat san hoc"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("te sach han ky thuat do hoc") OR ("tu can trinh kxy thuat san hoc")).
• Removing quotes may allow a broader search: (( te sach han ky thuat do hoc ) or ( tu can trinh kxy thuat san hoc )).
• Adding a wildcard symbol may retrieve word variants: (("te sach han ky thuat do hoc") or ("tu can trinh kxy thuat san hoc"))*.