Perhaps you should try some spelling variations:
parabolic differential » partial differential
differential equation » differential equations, difference equations
metabolic differences » metabolic disturbances, ethnic differences, metabolism references
differences equations » difference equations, difference equation, differential equations

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: (( parabolic differential equation ) OR ( metabolic differences equations )).
• Adding a wildcard symbol may retrieve word variants: (( parabolic differential equation ) or ( metabolic differences equations ))*.