The issue is that the columns specified in the Subset phrase were not the names of the columns in the data table. Your names are in French, so all that has to be done, is to change the names of the columns in the script to match the names in the data table.
Names Default To Here( 1 );
dt = Current Data Table();
dt << select where( :A > 20 & :A < 40 & :Date >= (Today() - In Weeks( 2 )) );
dtSub = dt << subset(
selected rows( 1 ),
columns( :Année, :B, :Quantième, :Mois, :Date, :Produit, :A ),
output table( "abc" )
);
Jim