At 41 kg for your height, you're quite underweight, so gaining weight needs more than just adding supplements. Ashwagandha, Zincovit and Pancharishta are generally safe OTC products on their own, but taking all three together isn't something to decide by yourself.
Next Steps
See a physician or dietitian to check why you're underweight, since causes like
thyroid issues or poor appetite need ruling out first. They can also confirm which of these three products you actually need, and the safe way to take them together.
Health Tips
Don't start all three together without medical guidance, particularly given how low your current weight is.