#What is KI-Na2S2O3 solution?
Read the question again, there is no KI-Na2
solutions, they are two different solutions. What you should be thinking is what is the significance of adding KI before reacting sodium thiosulphate with CuSO4
#the brownish precipitate is CuSO4+H2O?
Are you able to write the chemical equation for what is happening and see which precipitate is formed?
#the pale violet precipitate is 2Cu+(aq)+4I-(aq)=2CuI(s)+I2(s)?
#the precipitate in the filter paper i think is 2CuI+I2?
Be specific, don't quote 2 reagents or whole equation
Well it seems you don't understand the experiment you have done but take it slowly and think each steps and what could have been formed. Try to post what you think it is and we could confirm with you.