Search configuration
In the source site collection,
- Go to Site Settings > Export Search Configurations.
- Export to an XML file and copy to the destination farm.
In the destination farm,
- Go to Site Settings > Import Search Configuration
- Import the XML file.
In Site Settings,
- Go to Result Sources
- Perform a search crawl to add all the newly attached content to the index.
Note:
If you are copying data to a site collection that previously contained data, it is recommended to perform an index reset to clear out the data that is removed from the site but is still in the search index (i.e. this removes duplicate search results and non-existent items)