Hello @Lukáš Homola
Thanks for using Microsoft Q&A platform. I think you are looking for Spell Check API - https://learn.microsoft.com/en-us/azure/cognitive-services/bing-spell-check/overview
The Spell Check API lets you check a text string for spelling and grammar errors. This section provides technical details about the query parameters and headers that you use to request spell checking, and the JSON response objects that contain the results
Luckily, I find Spell Check API v7 now is supporting Czech lanague as below.
https://learn.microsoft.com/en-us/rest/api/cognitiveservices-bingsearch/bing-spell-check-api-v7-reference
I hope this provides some clues for your requirement.
Regards,
Yutong
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