Tesseract OCR Read Text from image

Question

I am using TesseractEngine for OCR read text for image , some time it is not working.

Problem reading bold number . Ex 666 9999 7777 . it is clear in image but OCR not able to red.

using (var img = PixConverter.ToPix(image))             
using (var page = engine.Process(img))
    ocrtext = page.GetText();