Perhaps you should try some spelling variations:
practical astronomy » positional astronomy
optical astronomy » spherical astronomy, positional astronomy
astronomy sergey » astronomy survey, astronomy surveys, astronomy seven
more practical » some practical
moore optical » moire optical, core optical, moon optical
more nautical » mile nautical, some nautical, board nautical
patrick more » patrick moyes, patrick mkie, patrick mark
more optical » moire optical, mode optical, core optical

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