This section details how to restrict search indexes to particular languages.
You do this by generating a partition using the "Assign Languages" tab of the
"Partition Indexes" view.
Simple Instructions:
To add a new language to partition by, use the "Assign Languages" tab to build
an index for it. Select the desired language from the "Language to add"
pull-down list and click "Add Language".
To remove a language, select it from the "Language Selection" list and click
"Remove Language".
To set the default language, select it from the list and click "Set Default".
To clear the default language, click "Clear Default".