display data from 2 dataset into 1 dataset in crystal report simultaneously

display in crystal report
on merging  i get data display from 1st ds after its finished then data is displaying from 2nd ds.it does not start from 1st page itself.
i need the result like this
eg  ds1           ds2
 sno name class      group
 1   a      1           red
 

but it shows like this

eg  ds1           ds2
 sno name class      group
 1   a      1          





10    k      3       
-ds1 last rec
11                red


ds1 is holding grid 1 and ds2 is binded with grid2 now in crystal report as told to merge i merged but it show ds1 first then after last record it continues with 2nd dataset data ..

i am calling the session values which holding the data from grid

 Dim ds As DataSet = DirectCast(Session("datasource"), DataSet)
        Dim ds1 As DataSet = DirectCast(Session("datasource1"), DataSet)

        ds.Merge(ds1)
Report1.SetDataSource(ds) 
here also it shows the same in ds   ds first then  continuing with ds1
pls suggest .thanks in adv