Perhaps you should try some spelling variations:
trinh nghien » kinh nghiem, trinh thiet, trinh dien
hanh trinh » canh tranh, hanh chinh
trinh phap » trinh phan, trinh han, trinh chat
trinh nghe » trinh he, trinh nha
co hanh » co thanh, co phanh, co anh
phap tu » phan tu, pham tu
tu hoc » te hoc
du hoc » duoc hoc

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (( co hanh trinh phap tu hoc ) OR ( duy khanh ((trinh nghe) OR (trinh nghien)) du hoc ))~.
• Adding a wildcard symbol may retrieve word variants: (( co hanh trinh phap tu hoc ) or ( duy khanh ((trinh nghe) or (trinh nghien)) du hoc ))*.