Perhaps you should try some spelling variations:
"te sach trinh nghien duoc hoc" » "te sach trinh nghe duoc hoc", "te sach kinh nghiem duoc hoc", "te sach trinh thiet duoc hoc", "te sach trinh nghiem duoc hoc", "te sach trinh nghia duoc hoc", "te sach tranh nghien duoc hoc", "te hanh trinh nghien duoc hoc", "te sach kinh nghien duoc hoc", "te sach trinh nghien quoc hoi", "toc sach trinh nghien duoc hoc"
"su khanh trach nhiem thu hoi" » "su khanh tra nhiem thu hoi", "su khanh trac nghiem thu hoi", "su khanh trach nhiem thuc hoi", "su khanh trach nghiem thuc hoi", "su khanh trach nghiem thi hoi", "su thanh trach nhiem thu hoi", "vu khanh trach nhiem thu hoi", "su khang trach nhiem thu hoi", "su khanh trach nhiem thu hoai", "su khanh trach nhiem thu phoi", "su khanh trach nhiem thu hai"

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: (("su khanh trach nhiem thu hoi") or ("te sach trinh nghien duoc hoc"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("su khanh trach nhiem thu hoi") OR ("te sach trinh nghien duoc hoc")).
• Removing quotes may allow a broader search: (( su khanh trach nhiem thu hoi ) or ( te sach trinh nghien duoc hoc )).
• Adding a wildcard symbol may retrieve word variants: (("su khanh trach nhiem thu hoi") or ("te sach trinh nghien duoc hoc"))*.