Perhaps you should try some spelling variations:
practical astronomy » nautical astronomy
optical astronomy » nautical astronomy, spherical astronomy
moore positional » aware positional, pure positional, whole positional
astronomy sergey » astronomy survey, astronomy surveys, astronomy seven
patrick mkie » patrick mackie, patrick mein, patrick m
mkie optical » moire optical, mode optical, more optical
patrick meek » patrick meier, patrick mein, patrick meir
patrick mark » patrick marx, patrick burk, patrick mr

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