Index & Match with dynamic list of data : Retrieve data and classify by dates ?

Hi there
I have two sheets. On the first one I have one column with the dates and another one with the corresponding data.
In sheet2, I want to retrieve the data, depending on the dates I choose.
> I enter the dates in column A, then in B I have all the dates and in column C I have entries corresponding to the dates.
My pb is that I can't manage to find a formula that will handle the dynamic range (as depending on the dates for which I want to retrieve the data, the number of entries corresponding to the dates can be different, as the data..The "size" is constantly moving)

Thanks for your input on this, attached an example.

Thanks