Material texture error

@First excuse my English, I do not speak English and am using google translator.
Hello guys someone could give me a help that?
Next, whenever I download some stuff on the net and paste in the Documents folder \ Unreal Projects \ Project1 \ Content \ stuff appears there along the texture but the material sí textures do not connect, just disappear blueprint of the material, someone you know to fix it? thank already

Use the proper import procedure?