About the search issue: You could show the address of your website on the video, that would make things very easy for people who watch the video and decide they want to check out your book. (The website should have easy-to-find info about your books and links to buy them, I assume you have that.)
My impression from reading about publishing (in other words no experience, just secondhand info
) is that social media works best for advertising if that's not the main thing you use it for. So, if you use a social medium to post about all kinds of things which interest you, and to read about things which interest you, and to follow interesting and likeminded people, then you posts about books you've written are more likely to gain traction.