Perhaps you should try some spelling variations:
astronomy surveying » astronomy during
astronomy sergey » astronomy survey, astronomy surveys, astronomy seven
moore positional » aware positional, pure positional, whole positional
moore practical » moocs practical, mouse practical, course practical
more practical » some practical

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 ((moore practical) OR (more practical)) astronomy sergey ) OR ( the patrick moore positional astronomy surveying )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( the patrick ((moore practical) OR (more practical)) astronomy sergey ) or ( the patrick moore positional astronomy surveying ))".
• Adding a wildcard symbol may retrieve word variants: (( the patrick ((moore practical) OR (more practical)) astronomy sergey ) or ( the patrick moore positional astronomy surveying ))*.