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
thuoc sach » hoc sach, nuoc sach, thuat sach
nghien du » nghiep du, nghien cuu, nghiem dau
nhiem dai » nhien dai, nhiem tai, nghiep dai
thu sach » tu sach, thuat sach, thu hoach
ly hanh » ly anh, ly hang, lu hanh
du hoc » tu hoc, duoc hoc

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

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