To improve the reliability of the Tesseract OCR I can recommend trying the following:
** Experiment with the Scale option, try various values between 4 and 10.
** Use whitelist characters where possible. For example, if you are reading a decimal value field your whitelist should be set to ""0123456789.""
** If colours seem to be impacting your results, have you tried converting your image to B&W before performing OCR on it?
** If you are reading text for some kind of comparison rather than for data entry elsewhere than using some kind of Approximate Matching algorithm to compare is possible, this will reduce the need for 100% accuracy in what you read using OCR.
The true answer to your issue is to have font smoothing turned off, as Recognise Text is reliable in reading known fonts, OCR can only ever be used in some use cases after extensive testing to ensure accuracy.