Fix Java/Spring Backend Issues & Search Errors

I've got a Java/Spring Backend and an Angular frontend with a malfunctioning search functionality powered by Elastic Search, and I need an expert to help resolve these issues.

- Backend Problem: The issues are primarily stemming from the Backend, which is built with Java and Spring.
- Search Issues: The search functionality is giving incorrect results, which is obviously an issue that needs to be resolved.
- Data Types: The data being searched is mixed - both textual and numerical data.

Please, only apply if you have significant experience with Java, Spring, and Elastic Search, and can demonstrate a history of resolving similar issues.