Weird behavior with AR language

Hi,

I have tried your plugin to debug a discrepancy in search result numbers on our dev website, but I can’t seem to get results out for the AR language.

english results for Mosaic: https://dev.syrian-heritage.org/?s=Mosaic (a certain amount of results)
arabic results for mosaic: https://dev.syrian-heritage.org/ar/?s=%D9%81%D8%B3%D9%8A%D9%81%D8%B3%D8%A7%D8%A1 (a certain amount of results)

english API results for mosaic: https://dev.syrian-heritage.org/wp-json/relevanssi/v1/search?lang=en&keyword=Mosaic (a certain amount)

arabic API results for mosaic: https://dev.syrian-heritage.org/wp-json/relevanssi/v1/search?lang=ar&keyword=%D9%81%D8%B3%D9%8A%D9%81%D8%B3%D8%A7%D8%A1 (no results, this is the unexpected behavior)

Maybe I am passing some parameters the wrong way / overlooking something?

Can you please p

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