As others have said, ripgrep et al are faster than regular grep. You would probably also get much faster results with an alias that excludes directories you don't expect results in (I.e. I don't normally grep in /var at all).

I have seen some recommendations for recoll, but I haven't used it so can't comment. Anecdotally, I normally just use ripgrep in my home directory (it's almost always in ~ if I don't remember where it is). It's fast enough as long as my homedir is local (I.e. not on NFS).