There are several modes of vim, such as normal (normal mode), insert (insert mode), command line Mode, visual (visual mode). The same commands and shortcut keys function differently in different modes, so help information is also sub-modal.
Give me a chestnut:
What are the available values for BACKSAPCE when I want to see the set backspace?
If you're using: Help BACKSPACE, you can't find the answer, because here's how to find helpful information in normal mode
Use: Help ' backspace ', or use: Help backspace? , you will find the answer as it is, as this is the information for finding the operation settings.
Specific commands to use: Help helps yourself to see
Here are some references, hehe
: H:r represents help in finding command-line mode
: H R means find help in normal mode
: H v_r to find help information in visual mode
: H I_ctrl_w to find help for shortcut keys in insert mode
: H C_ctrl_w to find help for shortcut keys in command line mode
: h/\r Regular expression to find search
: h ' Ro ' indicates find operation Help information
: H-r represents a help letter for finding parameters
Search for help information for different modes in VIM