Perhaps you should try some spelling variations:
astronomy surveying » astronomy during
astronomy sergey » astronomy survey, astronomy surveys, astronomy seven
moore practical » moocs practical, course practical, before practical
mouse practical » course practical, rouses practical, use practical
more practical » some practical

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