Perhaps you should try some spelling variations:
optical astronomy » nautical astronomy, spherical astronomy, positional astronomy
astronomy sergey » astronomy survey, astronomy surveys, astronomy seven
patrick more » patrick moore, patrick moyes, patrick mkie
more optical » moire optical, core optical, more optimal

You may be able to get more results by adjusting your search query.

• Adding a wildcard symbol may retrieve word variants: the patrick more optical astronomy sergey*.