Snapchat account must have a full name in order to do this.
- Load Snapchat
- Search for the Name You Want
- Either copy or screenshot the full name. for example: Christopher
- Go to any database leak page for example: http://www.leakbase.pw
- put “Christopher” in the first name section
- then put “lewis” in the last name section
- find results
- check all passwords.
Some may not work, but it has worked for me.