In food shop, we see many fold ridges on crispy chicken like this Picture:   While googling about the secret, I found most of them advised to put the chicken pieces in a bag after dipping it in the butter, then shake, dip and re shake. But in practical, this shaking process does not create ridges structure [Like in the above picture]. In many youtube videos, although at the beginning of the video, it is showing ridges picture, but after completion of the video, the chicken pieces do not cover with ridges. Some other advised to use corn flakes to make these ridge structure. But corn flakes are expensive.  My question is how to make these ridges without corn flakes? Is there any alternative or real video tutorial? 
There are lots of potential thickeners, but you often need to select the one that works best with your given need (temperature, if it has dairy, resulting mouthfeel, etc).  In your case, you're already using rice, so you may want to stick with a starch -- corn starch, potato starch, tapioca, etc.  For these, you add a bit to cold liquid, mix it well, add it to the soup and heat it up.  As it approaches boiling, it'll thicken.  You can use flour (wheat, rice, yam, etc.), but in the case of wheat flour and possibly the others, you may have to deal with a raw taste.  You fix this by cooking the flour with butter or oil into a roux, and then adding that, and heating it up to a near boil.  You can also use pureed vegetables.  Cook them in the soup, then put it through a blender so the vegetables add body to the soup. 