Update cheatsheets

tldr/linux/cmus

@@ -8,9 +8,9 @@ source: https://github.com/tldr-pages/tldr.git
 > Command-line Music Player.
 > Use `<ArrowKeys>` to navigate, `<Enter>` to select, and numbers `<1>`-`<8>` switch between different views.
 > See also: `ncmpcpp`, `clementine`, `qmmp`.
-> More information: <https://cmus.github.io>.
+> More information: <https://manned.org/cmus>.
 
-- Open cmus into the specified directory (this will become your new working directory):
+- Open `cmus` into the specified directory (this will become your new working directory):
 
 `cmus {{path/to/directory}}`
 
@@ -18,6 +18,14 @@ source: https://github.com/tldr-pages/tldr.git
 
 `<:>add {{path/to/file_or_directory}}`
 
+- Refresh the metadata of songs in the library:
+
+`<:>update-cache`
+
+- Search for songs, albums, or artists:
+
+`</>{{something}}`
+
 - Pause/unpause current song:
 
 `<c>`
@@ -26,6 +34,6 @@ source: https://github.com/tldr-pages/tldr.git
 
 `<s>`
 
-- Quit cmus:
+- Quit `cmus`:
 
 `<q>`