Need Help with Multilingual Retrieval in Vertex AI Agent Builder

Hi,

I'm building a multilingual chatbot using Creating Data Store, Discovery Engine, and Reasoning Engine.

Right now, I have one data store that contains both English and German documents. The problem is: when I ask something in English, it doesn't retrieve relevant content from the German documents — even if the answer is there.

I'm looking for a solution where the retriever can search across both languages.
For example: if the query is in English, it should also check German documents and return the right response if available.

Any suggestions or best practices would be really helpful!

未识别出任何仓库文件、测试或代码入口；该报告请求针对 Vertex AI Agent Builder 中共享数据存储上的多语言检索提供指导。由于 issue 没有提供完成标准，请首先确认是否需要进行具体的 SDK 更改或编写可复现的测试。

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