I want to get this off my chest

There is this Akijom last name family who stay on 3rd floor single bedroom house in Bengaluru. They said they are meities. They told our landlord they are three, but there are atleast 6 people in that house. I haven't told this to my landlord. Now this is want I want to get it off my chest, every time these girls pass our floor and if one of us are outside they say some shit to eachother and keep giggling, they do it often and literally always...it's like they want to make it obvious to me they are laughing at me. I hate this coz I can't say or ask anything, can't go tell my landlord coz he will say how do you know what they are saying. Anyone who knows any akijom staying on a third floor in bangalore, please tell them not to. This is confusing for over an year since they came.