Perhaps you should try some spelling variations:
practical astronomy » optical astronomy, positional astronomy
astronomy surveying » astronomy during
astronomy survives » astronomy survey, astronomy surveys, astronomy studies
del practical » dll practical, model practical, daml practical
dale nautical » mile nautical, tables nautical, a nautical
patrick dale » patrick case, patrick de, patrick calder
patrick del » patrick de, patrick dobel, patrick daly

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 del practical astronomy survives ) OR ( the patrick dale nautical astronomy surveying )).
• Adding a wildcard symbol may retrieve word variants: (( the patrick del practical astronomy survives ) or ( the patrick dale nautical astronomy surveying ))*.