I would say, check the data in there.
If it's closed already it's probably a leak.
If it's still open it's either :
1. Testing server with no important data
2. Honey pot servers, waiting for project like us to pick on them and collect our scanners IPs.
3. Really careless people
The search functionnality is provied by a third-party software.
That's what allows us to run quickly on such small hardware for now (fast indexing), but it's clearly not friendly with user inputs.
We noted this is the main concerns about our users right now and will do some research on how to improve it !
Thanks