May I help you in Hindi
It is pretty simple and easy to understand how to say may I help you in Hindi. Unlike other Hindi phrases that have some different meanings when it comes to content and context, this one is pretty straight-forward.
This version is a male. If a female is to say the same Hindi phrase, the second-last word of the line will be changed to सकती (Sakatī) and all else will remain same.
At the same time, it is a bit formal. The third word of this phrase may change to तुम्हारी (Tumahārī) or तेरी (Terī), which will make it a bit more informal.
However, this sentence itself is very formally used and therefore you can stick with the original Hindi translation only.