Perhaps you should try some spelling variations:
practical astronomy » nautical astronomy, optical astronomy, positional astronomy
astronomy survey » astronomy surveys, astronomy sergey, autonomy survey
mayen practical » man practical, modern practical, seven practical
patrick mayen » patrick bayer, patrick madan, patrick moyes

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

• Adding a wildcard symbol may retrieve word variants: the patrick mayen practical astronomy survey*.