Are ChatGPT responses different depending on the language used? Does it research sources specifically within the language the user asks a question or does it not matter?

So while using the deep research feature, i noticed that when i spoke in portuguese asking for it to research a topic, it only gave me portuguese websites as sources used in research, and in the "thought process" window it seemed to only be retrieving info from those sites

This would obviously reduce the pool of websites it can retrieve information from, as compared to if i asked it something in english right? because there are usually far more websites, articles, papers, etc in english than there would be most other languages in most topics, so quality of answers would be worse if user talks to chatgpt in other languages?

or is the thought process window all fake, and it researches in any language of it's database but only gives me sources in the language i used?