Submit a FOIA for a specific area and time, and you can get all of the raw data for that, then you can do your own searches. You generally cannot submit a FOIA for all of the data.
The reason I'm skeptical of this, in this particular case, is because the data here isn't actually owned by the police/government (I think?), it's owned by Flock. A department can search the data for given attributes, but I don't think they have the whole data set to provide as a response to a FOIA request in the first place.
I don't have a source on hand but I do remember seeing a recent case on this stuff that indicated that "even if they're paying Flock to store it, it's still the government's data"