Perhaps you should try some spelling variations:
practical astronomy » optical astronomy, positional astronomy
astronomy sergey » astronomy surveys, astronomy seven, astronomy society
astronomy survey » astronomy surveys, autonomy survey, astronomy surveying
moocs practical » books practical, mics practical, colts practical
astronomy large » astronomy line, astronomy long, astronomy charles
moocs nautical » logs nautical, nos nautical
patrick moocs » patrick moore, patrick mons, patrick moyes
hoc nautical » nos nautical, hoc analytical, logs nautical
patrick hoc » patrick home, patrick hanc, patrick c

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