As available Liquid output increases with every feature you include in the Page, the best place to look for documentation is in the Feature's Documentation- in this case Site Search32. However, I can see that the desired information is not there in this case! I'll investigate and update it for you.
For developers who prefer to tinker and explore for themselves, we have also now added a series of Articles in the Developers Section of the Docs which explain fully how to use Liquid Dot Notation to find out all the possible live Liquid output on your Page. You can start learning here: https://siteglide.support/en/articles/3574387-getting-started-with-liquid-dot-notation-tutorial33
Hope this helps!