Hello guys

I am new to maya but i know how to texture a little object and using the UV texture but what i don't understand is why when i import a texture object into another scene which have a already texture object in it . The import object's texture change it texture to be the same as the one already in the scene

do i have to use different texture like use one with phong and the other with lambert or something or do i need to make each of object use different shader which i don't know how to do it

It would be really great if someone explain or show me how to fix the problem or show me a video . thank you.