Perhaps you should try some spelling variations:
optical astronomy » nautical astronomy, spherical astronomy, positional astronomy
practical economy » political economy, practical astronomy, practices economic
astronomy during » astronomy dialling, astronomy meeting, economy during
economy studies » economic studies, economy stupid
de practical » de practicas, e practical, de practica
patrick mons » patrick moyes, patrick bond, patrick mpondo
mons optical » ions optical, mono optical, loss optical
patrick de » patrick d, patrick dr, patrick dale

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 de practical economy studies ) OR ( the patrick mons optical astronomy during )).
• Adding a wildcard symbol may retrieve word variants: (( the patrick de practical economy studies ) or ( the patrick mons optical astronomy during ))*.