Here's the format: [sampleset]-hit[sampletype].[file extension]
With [sampleset] being Normal, Soft and Drum, while [sampletype] being Normal, Whistle, Finish and Clap and [file extension] being .wav/.ogg/etc.
For example, if you want to use a .ogg file as a normal sound of Soft sample, then the format would be soft-hitnormal.ogg
Also if you do not have file extension visible just skip the [file extension] part.