Perhaps you should try some spelling variations:
astronomy survives » astronomy survey, astronomy studies
astronomy surveys » astronomy survey, astronomy surveying, autonomy survey
astronomy sergey » astronomy survey, astronomy large, astronomy society
moocs practical » books practical, mics practical, colts practical
astronomy seven » astronomy some, astronomy science, astronomy between
patrick moocs » patrick moore, patrick mons, patrick moyes

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 seven) OR (((astronomy survives) OR (astronomy surveys))))) OR (astronomy sergey)).
• Adding a wildcard symbol may retrieve word variants: the patrick moocs practical ((((astronomy seven) or (((astronomy survives) or (astronomy surveys))))) or (astronomy sergey))*.