Can we have 3 connection using parameters ?

Hello, here's my problem:

I've a Json connecton that recieve from a REST service, I perse them and I make an other Json string to get only the field that I want. 
I wanna make 2 charts; a piechart of the used extention, and a linechart for the usage in the past month. here's my json 

[
{"extention":"zip","label":"9,09 %","value":6},
{"extention":"rtf","label":"34,85 %","value":23},
{"extention":"doc","label":"6,06 %","value":4},
{"count":27,"day":"02/09"},
{"count":1,"day":"02/08"},
{"count":5,"day":"02/07"}
]

I've seen that if I want to make 2 charts, i must have all the fields in every object.

So I thought to make 2 other reports and put these into my summary reports with subreports.
But the thing is that if I want to separate the data, i must separate the connection.
So I tried to put into 2 params, 2 JsonDataSource but it won't work

I tried for a week now, i depresed ...

Can you help me ?

regards Gilles