How do I search through multiple repositories connected to one repository?

[00mucho00]

Hi, i'm not the most proficient in coding in markdown, using ruby or anything similar, but I've been working on setting up a website/wiki for my TTRPG system, one of the most important things for me is managing to set up search. The issue is, search does work, but it only searches only one repository, let me give an example:

• On the main repository and website e.g. this website, https://www.metanoia-engine.com/, this is under a separate repository
• I search for "Elf", which is located in another repository (which is actually all under the same website, but not repo), specifically https://www.metanoia-engine.com/rulebook-races
• No results found when searching on https://www.metanoia-engine.com/
• 1 result found when searching on https://www.metanoia-engine.com/rulebook-races

I hope my words are making sense, but if need be i'm happy to screenshot the issue that i'm trying to explain.

Sorry to bother if this is a very simple question/fix, I just am unable to find this specific instance elsewhere.