Perhaps you should try some spelling variations:
trinh nghien » trinh nghe, kinh nghiem, trinh thiet
nghien khien » thien nhien, thien chien, nghe phien
trach nhiem » trac nghiem
hanh trinh » canh tranh, hanh chinh
sach trach » sach tranh, sach truc, sat trach
khien hoc » nhiet hoc, dien hoc
nhiem dan » nghiem ban, nghiem van, nghiem dau
lu hanh » luu hanh, du hanh, ly hanh
tu sach » thu sach, su sach, te sach

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( lu hanh trinh nghien khien hoc ) or ( tu sach trach nhiem dan toc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( lu hanh trinh nghien khien hoc ) OR ( tu sach trach nhiem dan toc )).
• Adding a wildcard symbol may retrieve word variants: (( lu hanh trinh nghien khien hoc ) or ( tu sach trach nhiem dan toc ))*.