my wife does not know how to negotiate, multiple times have i said to her that she should fight for more, but she will not or does not know how to do it.

but there is also another side. women that i have worked with have used social norms to ask for more. like in some conversation make a joke about how they deserve promotion and pay incrase, like hehe im such a great team member/worker i deserve a pay incrase, wink wink, and such comments multiple times. I never heard a man use this method. If its from a man then he asks to speak to you and directly says what he wants.