As if it has to start with what we are searching and the what we are searching for cannot be between any characters.
That's exactly the way the search works by default.
Try adding the wildcard operator *, i.e. enter *628 (and read the documentation to get familiar with other search operators that you may find helpful).
That suggestion is exactly what we were looking for. Adding the asteriks in front of the search appears to return all relevant records. Thanks!