What voice? I just tried it using Microsoft James, a One-Core voice, and it pronounces chhota with the opening sounding like church in English. Are you looking for the sound like at the beginning of cotton?
No matter what it is you're trying to achieve with a specific synth and voice as far as tweaking how a given word is pronounced, you will use the Voice Dictionary for that voice and then start playing with "made up spellings" as the replacement for the real one that the synth pronounces using that voice the way you wish it to be pronounced. It's trial and error.
Brian - Windows 10 Pro, 64-Bit, Version 1809, Build 17763
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