A.Cuba in Chevrolet Corsa Classic 1.6

Good night people. My corsa pulls the air conditioning. First it was done a vacuum test and then load with R134a. It does not cool what it should. It has the new avitaculum filter. The electro fans perfect, radiator without dirt. The only thing is that by emptying the pipe, a lot of green liquid that is used to see leaks. Could this liquid be bad? Or could I have something else? Who is doing the job is new in this. Thank you already