Quick answer: Change the setting Limit available chords in General Settings.
Limit available chordsLiquid Notes, by default, only shows a limited set of available chords in the list for substitution. This is to not overwhelm you with the full range of possibilities the theory of harmony provides, instead rather to offer only those that expert composers find as 'safe' (from the perspective of making changes to your arrangement).
However, you may change this behavior of Liquid Notes at any time by changing the setting Limit available chords in General Settings.
Here is a screen shot of this setting:
Find the setting Limit available chords at the upper end of the Settings window, in the frame General Settings.