Perhaps you should try some spelling variations:
structures microscopy » structure microscopy, structure spectroscopy, nanostructures microscopic
structure microscopic » structure microscopy, structure spectroscopic, culture microscopic
reference python » reference method, reference author, reference edition
python programs » python program, action programs, method programs

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "reference python programs ((structures microscopy) OR (structure microscopic)) https~".
• Adding a wildcard symbol may retrieve word variants: reference python programs ((structures microscopy) OR (structure microscopic)) https*.