What do you do When trying to find the right audience for your product and keep your audience interests.... do you keep it general or do you go into specifics?

In response the gaffer to her Publication

For Example when selling some fashion items say women’s jewellery, you target gender sure, but interests wise do you target the “jewellery” interest as a whole or target interests like “Pandora Jewellery” or “Tiffany and Co Jewellery” or would you target even more specific and go for really specific interests and filter them for age gender etc etc.