Okay thanks for your comment, seems like this is basically about filtering an array, here is my proposal:
var arr = collectionGenerated.where(name: 'attribute');
var result = $.grep(arr, function(val) {
return val.itemId == 'attribute';
});
result being the array containing only what fits both filters.
-- EDIT --
i guess in your data structure it is
var result = $.grep(arr.sections, function(val) {
return val.itemId === 'inicio';
});