Perhaps you should try some spelling variations:
trinh nghien » trinh nghe, kinh nghiem, trinh thiet
trach nhiem » trac nghiem
hanh trinh » canh tranh, hanh chinh
nghien de » nghiem de, nghiep ke, nghiem d
nhiem dau » nghiem dau, nhiem mau, nghiep dau
thu sach » thuat sach, thuoc sach, thu hoach
lu hanh » luu hanh, du hanh, ly hanh
tu sach » su sach, te sach, tu cach
dau hoc » dai hoc, du hoc, dan hoc
de hoc » te hoc, du hoc, dien hoc

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 de hoc ) or ( ((thu sach) OR (tu sach)) trach nhiem dau hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( lu hanh trinh nghien de hoc ) OR ( ((thu sach) OR (tu sach)) trach nhiem dau hoc )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( lu hanh trinh nghien de hoc ) or ( ((thu sach) OR (tu sach)) trach nhiem dau hoc ))".
• Adding a wildcard symbol may retrieve word variants: (( lu hanh trinh nghien de hoc ) or ( ((thu sach) OR (tu sach)) trach nhiem dau hoc ))*.