Perhaps you should try some spelling variations:
moocs positional » holds positional, blocks positionals, images positional
astronomy sergey » astronomy surveys, astronomy seven, astronomy large
astronomy survey » astronomy surveys, autonomy survey, astronomy surveying
moore nautical » mile nautical, moore national, some nautical
board nautical » board practical, board national, board neutral
patrick moocs » patrick mons, patrick moyes, patrick moore's
patrick board » patrick bond, patrick hubbard, patrick leonard

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