Perhaps you should try some spelling variations:
"potential differential equations" » "potential differentiation equations", "potential difference equations", "potential differences equations"
"partial difference equations" » "potential difference equations", "racial differences equations"

Try widening your search to All Fields.

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: (("partial difference equations") OR ((((("potential differential equations") OR ("partial differential equations"))) OR ("polynomial differential equations")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"partial difference equations\") or (((((\"potential differential equations\") OR (\"partial differential equations\"))) or (\"polynomial differential equations\"))))".
• Removing quotes may allow a broader search: (( partial difference equations ) or ((((( potential differential equations ) OR ( partial differential equations ))) or ( polynomial differential equations )))).
• Adding a wildcard symbol may retrieve word variants: (("partial difference equations") or ((((("potential differential equations") OR ("partial differential equations"))) or ("polynomial differential equations"))))*.