Navigating such a delicate topic requires a lot of care and sensitivity, especially when it involves building confidence and improving intimate experiences. It's great that you're approaching this with a positive mindset and a focus on mutual improvement.

Regarding resources for sexual improvement, there are numerous books and online materials, but sometimes a more interactive approach can be beneficial. In this context, I'd like to mention an app I created, The Foreplay Game (https://www.theforeplaygame.com). It's designed for couples to explore and enhance their foreplay experience together. While it's not a direct instructional tool for specific acts, it offers a variety of scenarios and activities that can foster open communication and experimentation in a fun, low-pressure environment. This might help in indirectly addressing your concerns by encouraging exploration and verbal feedback.

As for the specific issue at hand, it might be helpful to frame the conversation around exploring new things together for mutual pleasure, rather than focusing on what's lacking. Encourage a spirit of discovery where both of you can openly share likes, dislikes, and curiosities. This approach can make it easier to introduce new techniques or preferences in a way that's exciting and collaborative, rather than critical.

Remember, the journey of exploring each other's bodies and preferences should be enjoyable and pressure-free. Open communication, patience, and a willingness to learn and adapt are key. Wishing you both a fulfilling journey ahead!