I often want to write commands like this (in zsh, if it\'s relevant):
zsh
find | \\ grep stringinfilenamesIwant | \\
As you are already using GNU find you can use its internal regular expression pattern matching capabilities instead of these grep, eg:
find
grep
find -regex ".*stringinfilenamesIwant.*" ! -regex ".*stringinfilesnamesIdont.*" -exec dosomecommand {} +