Perhaps you should try some spelling variations:
"put–call parity" » "put–call party", "put–call parts", "put–call paris", "put–cell parity", "put–hall parity", "put–fall parity"
"put–all parity" » "put–all party", "put–all parts", "put–all paris"
"put–all part" » "put–all parts", "put–all pairs", "put–all pass"

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: (("put–call parity") OR ((("put–all parity") OR ("put–all part")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"put–call parity\") or (((\"put–all parity\") OR (\"put–all part\"))))".
• Removing quotes may allow a broader search: (( put–call parity ) or ((( put–all parity ) OR ( put–all part )))).
• Adding a wildcard symbol may retrieve word variants: (("put–call parity") or ((("put–all parity") OR ("put–all part"))))*.