This phrase is used in a pejorative way, by some men in Argentina, to talk about the trivial things, they believe,  women do or enjoy doing, like having “a crisis” when one nail chips off before a rdv, or spending days window-shopping until they find the right dress for a party. 

Being a feminist myself, knowing that women nowadays engage in serious causes, I decided to ironically “play the game” and portray these “cosa ‘e minas (women’s stuff). Because when you are sure of who you are, of what you do, you do not feel ashamed of your feminine part. On the contrary, you cherish it!