Very magic mode treats every character apart from letters, numbers, and underscores as a special character.
You can set very magic mode for a command by prefixing your regex strings with \v (for example, /\vfoo or :s/\vfoo/bar).
Very magic mode is often used when many special characters are to be used. For instance, we used the following example to replace cat hunting mice with mice hunting cat:
:s/\(cat\) hunting \(mice\)/\2 hunting \1
In very magic mode, this can be rewritten as follows:
:s/\v(cat) hunting (mice)/\2 hunting \1