My snippets are gone, how can I get them back?

TextExpander v.5, v.4, v.3 

Restore lost snippets:  

1. Open TextExpander so that  it appears in the menu bar. TextExpander must be visible in the Dock for this to happen, if it is not choose  Preferences > Appearance and  uncheck 'Hide in Dock'.
2. In the menu bar choose File > Restore Data from Backup and select the most recent file with the largest snippet count.

If you do not have TextExpander set to make backups, turn that setting on in Preferences > Backup. 

TextExpander v.2

Restore snippets in TextExpander 2, or if restore didn't work in v5, v4, v3, from your own backups or Time Machine. 

Not sure what version of  TextExpander you are using?