$ http.get ('{{path ("error in the path

Hi, I'm new using AngularJs and I can not pass variables to php Silex, if you catch them but when I do the function, the route does not take them

Launches this error:

  

link

and when I do it directly with an action

  

link

but I do not want it that way because I have it in a json

function buscar() {
        $http.get('{{ path("admin.filtro") }}', { params: vm.filtro })
            .success(function(data) {
                if (data.status == "success") {
                    vm.registros = data.registros;
                }
            })
            .error(function(err) {
                console.log(err);
            });
    }