But what about it´s effect as a "vein enlarger or relaxer" (I don´t know the english for "vasodilatador" in portuguese)?
A vasodilator is a blood vessel relaxer.
But varicose veins are not caused by relaxation of the veins but rather a loss of elasticity. You know how your underwear will not stay up when the elastic wears out and the waist band stretches? This is like what happens with varicose veins. The veins lose their elasticity and the veins stretch out and stay stretched out, called varicosing.
Normal, healthy veins will relax and contract as needed controlling blood flow.