Knowledge can be obtained in any language. Some languages are quite robust and deep, while others may be more shallow and limited in scope, but there are opportunities for the acquisition of knowledge within any language. Knowledge is an overall term for the understanding of something, whether it be concrete or intangible. Even in shallow languages, the people have knowledge of their ways and environment and this can be passed on to others.
I definitely believe that language can be obtained in any language. I do not believe that language is the barrier in which knowledge can be obtained. There is more than one language on this planet that is exclusive to something a such as that. Knowledge is something that can be learned despite what you speak.
The limitations of some languages make it difficult to learn abstract concepts. People that do not have words for things like lakes because their land has no still water, only rivers, will have to make up new words or use alien ones. There are other concepts like medicine and math that have their own language. Language can be a barrier, but not an unbreachable one.
yes, i do think that a lot of knowledge can come from any language or any person that you might be talking to. I think that we can pick up more knowledge at any time, and that we are always getting smarter as we are going through our own life.
The linchpin of this debate is how we define language. The easiest way to illustrate that knowledge cannot be obtained in any language is to consider an extinct language. Weyto is a language named after a tribe in Ethiopia. The language has not been spoken since at least the 18th century. No one denies that the language once existed, but it would be impossible to obtain any knowledge in Weyto because there is no one alive who can speak it, read it, or decipher it. It would be akin to saying that there is knowledge to be gained from randomly organized letters and numbers.