Perhaps you should try some spelling variations:
"te sach ngan ly thuyet hoa hoc" » "te sach ngan ly thuyet va hoc", "te sach ngan ly huyet hoc hoc", "te sach ngon ly thuyet hoa hoc", "te sach nha ly thuyet hoa hoc", "te sach han ly thuyet hoa hoc", "toc sach ngan ly thuyet hoa hoc", "te sach ngan hay thuyet hoa hoc", "te sach ngan lan thuyet hoa hoc"
"te cac nganh ky thuat do hoc" » "te hoc nganh ky thuat do hoc", "te cac nganh y thuat do hoc", "te cac nganh xay thuat do hoc", "te cac hanh ky thuat do hoc", "te cac nganh ky thuat o hoc", "tu cac nganh ky thuat do hoc", "ve cac nganh ky thuat do hoc", "te cao nganh ky thuat do hoc", "te cac nganh ky thuat co hoc", "te cac nganh ky thuat do hoa", "te cac nganh 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 cac nganh ky thuat do hoc") or ("te sach ngan ly thuyet hoa hoc"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("te cac nganh ky thuat do hoc") OR ("te sach ngan ly thuyet hoa hoc")).
• Removing quotes may allow a broader search: (( te cac nganh ky thuat do hoc ) or ( te sach ngan ly thuyet hoa hoc )).
• Adding a wildcard symbol may retrieve word variants: (("te cac nganh ky thuat do hoc") or ("te sach ngan ly thuyet hoa hoc"))*.