Perhaps you should try some spelling variations:
trinh nghien » trinh nghe, kinh nghiem, trinh thiet
hanh trinh » canh tranh, hanh chinh
thi nghiem » thuc nghiem
nghien de » nghiem de, nghiep ke, nghiem d
thu sach » tu sach, thuat sach, thuoc sach
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: (( thuc hanh trinh nghien de hoc ) or ( thu sach ((thi nghiem) or (thieu nhi)) dau hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( thuc hanh trinh nghien de hoc ) OR ( thu sach ((thi nghiem) OR (thieu nhi)) dau hoc )).
• Adding a wildcard symbol may retrieve word variants: (( thuc hanh trinh nghien de hoc ) or ( thu sach ((thi nghiem) or (thieu nhi)) dau hoc ))*.