Perhaps you should try some spelling variations:
practical astronomy » nautical astronomy, optical astronomy, positional astronomy
astronomy studies » astronomy study, economy studies, astronomy status
astronomy surveys » astronomy survey, astronomy surveying, astronomy survives
moocs practical » books practical, mics practical, colts practical
patrick moocs » patrick moore, patrick mons, patrick moyes
patrick mayen » patrick madan, patrick moyes, patrick maxton
patrick bayer » patrick aher, patrick baert, patrick guyer

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: (( the patrick moocs practical astronomy studies ) OR ( the ((patrick mayen) OR (patrick bayer)) practical astronomy surveys )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( the patrick moocs practical astronomy studies ) or ( the ((patrick mayen) OR (patrick bayer)) practical astronomy surveys ))".
• Adding a wildcard symbol may retrieve word variants: (( the patrick moocs practical astronomy studies ) or ( the ((patrick mayen) OR (patrick bayer)) practical astronomy surveys ))*.