Perhaps you should try some spelling variations:
practical astronomy » nautical astronomy
optical astronomy » nautical astronomy, spherical astronomy
astronomy sergey » astronomy surveys, astronomy seven, astronomy large
astronomy survey » astronomy surveys, autonomy survey, astronomy surveying
more positional » pure positional, more positioning, aware positional
more practical » some practical
moore optical » moire optical, more optical, core optical
patrick more » patrick moyes, patrick mkie, patrick mark

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