Sometimes I’m missing certain special character in VIM/VI.
A short google search will probably provide the correct code to enter those, but there’s also a built-in way: digraph.
As soon as you enter the command
:digraphs in VIM, you’ll get a table of all available special characters and the code for how to enter it.
Remember that code (like two symbols), return to the edit and press
<ctrl>k + the two symbols in insert mode.
<ctrl>k + <symbol>
As usual, the help will also provide some useful information as well as symbols.