Teach yourself more about the tools you use, like frameworks, servers, OSes, editors, etc.
The notion of there being a wizened old man who just sits there and "knows everything about it" is, if not a myth, exceptionally rare.
Sure over time, bits stick and foundations build and you grow to be relatively expert on some topic. But if you stand still or grow too comfortable with what you've got, these days the world will move past and leave you behind.