It seems that Google has taken it upon itself to second guess the metadata it's given and has gotten it very wrong. We have half of our site not indexed, including the most critical product category pages because Google thinks women's jewellery is close enough to men's jewellery that it'll make the men's category pages the canonical for the women's category pages. We have the canonical set to self for each of the pages concerned as each is unique content. The URLs are obviously unique as are the titles, meta descriptions, breadcrumbs, and other page content. We want people to find the correct page if they search for "women's necklaces" versus "men's necklaces". How can we fix this?