Perhaps you should try some spelling variations:
hanh thiet » thanh thieu, hanh theo
kha trinh » qua trinh, ha tinh, tra trinh
thiet yeu » thiet ke, theo yeu
trinh tu » trinh ky, trinh do
don gian » dan gian
hoc giao » hoc cao
tu hanh » du hanh, lu hanh, thuc hanh
vu kha » vu kham, vu khac, vu khoa

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: (( vu kha trinh tu - don gian ) OR ( tu hanh thiet yeu - hoc giao ))~.
• Adding a wildcard symbol may retrieve word variants: (( vu kha trinh tu - don gian ) or ( tu hanh thiet yeu - hoc giao ))*.