Perhaps you should try some spelling variations:
trinh thiet » trinh viet, trinh thi
sach trinh » sach tranh, sach kinh, sach tren
hanh trinh » canh tranh, hanh chinh
nghien tu » nghien cuu, nghiep vu, nguyen tu
nghiep tu » nghiep vu, nghiep vua, nghiep cua
thiet yeu » thiet ke, theo yeu
te sach » toc sach
yeu hoc » yeu hoi, lieu hoc, yeu nuoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( te sach trinh ((nghien tu) OR (nghiep tu)) hoc ) or ( thuc hanh trinh thiet yeu hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( te sach trinh ((nghien tu) OR (nghiep tu)) hoc ) OR ( thuc hanh trinh thiet yeu hoc )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( te sach trinh ((nghien tu) OR (nghiep tu)) hoc ) or ( thuc hanh trinh thiet yeu hoc ))".
• Adding a wildcard symbol may retrieve word variants: (( te sach trinh ((nghien tu) OR (nghiep tu)) hoc ) or ( thuc hanh trinh thiet yeu hoc ))*.