let's know

Phrase

 * 1)  let's learn, find out, or see [about]
 * 2) * 2008, Amar Tyagi, Let's Know Handicrafts of India (Star Publications) ISBN 9781905863181
 * 3)  let us know, get back to us, keep us posted
 * 1)  let us know, get back to us, keep us posted