I’m researching a few niche topics where specialist publications and official documentation are much more useful than broad web results. Is there a practical way to ask Perplexity to stick to a list of domains, or to exclude certain sites from its research?

I’ve tried naming preferred sources in the prompt, but I’m not sure whether that reliably limits the search or just nudges the answer. How do you keep a Perplexity search focused without having to check every source manually?