Since you say, there is no fever and just a cold and a dry cough
, it might be due to allergy
precipitated by change of season.
You may give her Plain Cetirizine
syrup that comes in a strength of 5mg/5ml. You may give her 2.5ml twice a day for about 5 days.
Lozenges which have honey/ menthol etc will be good for her dry cough.
If she is not improving after 3 to 4 days, its better to have a word with your Pediatrician
Rinifol seems to have vitamins and probiotics- that is not going to help you with your present problem. Retherma contains paracetamol
also which might not be needed if there is no fever.
Hope my answer helps you.
Wish your kid good health.