You can import CSV files directly into an SQLite database. Then you are free to do whatever sql searches or manipulations you want. Python and golang both have great SQLite libraries from personal experience, but I'd be surprised if there is any language that doesn't have a decent one.
If you are running Linux most distros have an SQLite gui browser in the repos that is pretty powerful.
I'd be surprised if there is any language that doesn't have a decent one.
Yeah, SQLite provides a library implemented in C. Because C doesn't require a runtime, it's possible for other languages to call into this C library. All you need is a relatively thin wrapper library, which provides an API that feels good to use in the respective language.