Perhaps you should try some spelling variations:
door transport » poor transport, dots transport, lower transport
transport risk » transport crisis, transport air, transport back
risk across » risks across
our student » our students, your students, per student
ende door » ende der, one door
bis » bias
macro » micro

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: (( bis ende door transport risk across ) OR ( us our student teacher _ (macao OR macro) ))~.
• Adding a wildcard symbol may retrieve word variants: (( bis ende door transport risk across ) or ( us our student teacher _ (macao or macro) ))*.