The answer to your riddle, based on Jainism and the hints provided ("v thi shuru thaye" and "chaar akshar no che"), is Vairagya (વૈરાગ્ય).

Explanation:

• "Patni ne shringar ta Mane Keval Gyan" is a metaphorical way of saying: Just as a wife adorns herself, similarly, when one adorns (decorates) the mind with detachment (vairagya), only then can one attain Keval Gyan (omniscience).
• The word starts with 'V' (વ) and has four letters: વૈ-રા-ગ્ય (Vairagya).
• In Jainism, vairagya (detachment from worldly pleasures) is essential for spiritual progress and ultimately for attaining Keval Gyan.