Hi! I'm coming at this from a slightly different perspective because the other Advisors have hit the "which & why" ad placement side of your question. My angle is based on nearly 10 years hands on experience in "lifestyle enhancement" brand related e-commerce and fine jewelry distribution.
This seems like a product that should sell itself with an enormous mass market appeal. I wanted to take a look at a few things that could be affecting your disappointing conversion rate that could continue to play out regardless of spend or channel.
Is it easy to find?
Does the "hype" match the experience of the user?
Is the price point within reach of the target audience?
How simple/hard is it to place the order?
Is it "share-worthy" and easy to do it?
Assessment: Based on about 10 min of quick research - it's easy to find but the tops two links both give the customer reasons to abandon purchase fairly quickly. First, your product reviews are troubling - at almost 50/50 love it / disappointed. Second, your website landing page doesn't drive "buying" it encourages "browsing." The copy is fine but unnecessarily wordy and muddy. On the plus side, you have nice clean images of your products and clear relevant descriptions but the visual DISPLAY of it all comes across as "made in my living room" as opposed to a fashion oriented "lifestyle enhancement" brand for a woman who wants to keep her cool without sacrificing her style or professional image. Compared to other products in the marketplace hot Girls Pearls retails at an avg of about 10X to other "cooling" related products readily available in the market. Shopify/Amazon as shopping carts make it easy to purchase. Good call on those. Sharability is good with the ability to "pin" and "love" via open sky but could be enhanced with a few more "standard" options.
Recommendations: Before you invest another penny in marketing, I'd recommend a 5 specific actions to take that that would yield results you can test and track to optimize your click to sale ratio and could be implemented within 5-10 business days for about $500 bucks or less depending on what you can do yourself/with your current staff and/or who you outsource it to.
1. Drown OUT the negative reviews on Amazon. Ask your "fans" to post a review & offer an incentive to do it "now" with a clickable link to the product page.
2. Create a YouTube Channel for your company. Link all the videos on the web that have featured your product to it. Should take about 2 hours or less.
3. Get some "real women" video testimonials/endorsements produced that you can place on your site and your YouTube channel.
3. Mini Makeover for your website landing page to convert "window shoppers" to "impulse buyers" that is smartphone / tablet friendly, allows for A/B testing and captures analytics.
4. Take it down a notch on pricing if your margins can handle it. I'd take it down 20-25% across the board.
5. Add the ability to share via facebook, twitter and tumbler.
I would be happy to hop on a quick call to discuss further and direct you to some specific resources to get it done if you need them, just let me know.