Perhaps you should try some spelling variations:
"opera philosophical feminism" » "opera philosophical humanism", "opera philosophical darwinism", "opera philosophical pessimism", "opera philosophica feminism", "para philosophical feminism", "meta philosophical feminism"
"opera philosophia mechanica" » "opera philosophical mechanical", "opera philosophical mechanics", "opera philosophie mechanique", "opera philosophica mechanica", "opera philosophy mechanica", "pia philosophia mechanica"

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: (("opera philosophia mechanica") OR ("opera philosophical feminism")).
• Removing quotes may allow a broader search: (( opera philosophia mechanica ) or ( opera philosophical feminism )).
• Adding a wildcard symbol may retrieve word variants: (("opera philosophia mechanica") or ("opera philosophical feminism"))*.