If searching for application, it never stops. Al-tough that might arguable valid (aka: big repository to search, and/or continuously updated). It functionally is incorrect. Let's assume that is a bug, because it will cause the process being active and so a very high CPU load. In certain cases it may cause heating problems and defects to hardware. Note that this issue increases when running as virtual machine (Aka: guest-os in vbox). So a more proper behavior would be to wait for input [Search next button] from the user to continue searching after the first is found. For the case nothing (so far) found repository specific conditions (aka, 90% of apps searched) or a timeout (aka: 600 seconds) could be applied, A application dialog [Nothing found, so far: Continue searching? | Abort ?] would be the typical KDE user friendly way to do it. Note: No crash, so no stack trace included.
This was fixed for 5.15, the error should be much less important in 5.14 already. Sorry for the inconvenience.