Perhaps you should try some spelling variations:
practical astronomy » nautical astronomy, optical astronomy
astronomy sergey » astronomy survey, astronomy surveys, astronomy seven
more positional » pure positional, more positioning, aware positional
sole practical » solve practical, some practical, role practical
patrick sole » patrick boyle, patrick sahle, patrick scholae
patrick more » patrick moore, patrick moyes, patrick mkie

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 sole practical astronomy sergey ) OR ( the patrick more positional astronomy sergey )).
• Adding a wildcard symbol may retrieve word variants: (( the patrick sole practical astronomy sergey ) or ( the patrick more positional astronomy sergey ))*.