"kem cho ?" is used to ask how are you to elder or respected people while for younger one we ask "kem che?" "majama" is correct. "saaru chu" should be "saaru che" "tamara naam shu che ?" Here we say "Tamaru naam su che?" for elder or respected one and "taru naam su che ?" for younger one. "maru naam shweta che" is correct.

Kem chho ? = how are you ? Majhma / saru chhe = I am fine/good or everything's fine/good Use "Tamaru" instead of "Tamara", because 'Tamara' is a plural form. You can also use "Taru naam shu chhe ?" but you can use the word "Taru" only for people younger than you.