How to distinguish official LEGO mini movies from non-official movies? My sons (7 and 4.5 years old) love watching LEGO city mini movies on YouTube.

They love watching all kinds of LEGO city mini movies, such as: 

Arctic Explorers 



The Escape From Prison Island



Mountain Police Madness 



Gold Mine Grief



and many others...

We also bought them some of the sets featured in these mini movies.

The problem is that sometimes, when I search YouTube for LEGO city mini movies, some of the results shown are none official movies. While some are harmless movies of people showing how they build their LEGO sets, some are not appropriate for young children. 

One time we accidentally started watching a LEGO movie featuring some arctic explorers that encounter a frozen alien. It turned out to be an unofficial movie, which was too scary for our kids. We had to stop in the middle, and make up an alternative story to what happened on that movie.

My question is how can I reliably tell apart official LEGO city mini movies (all of which seem child friendly) from non-official movies. 

Is there some YouTube search that will only return official movies? Is there some listing with links to all the official movies?
Hello Eran's family! How are you all doing today?

Please try these methods instead:  


The Publisher's Home Page - DON'T go directly to the search box to search the term "LEGO city mini movies", but instead just
pull up one of your official LEGO mini movies and click on the
name of the person who published the video to YouTube.  

In this case it would be "LEGO". So, clicking on the content creator's name will
lead you to that publisher's homepage and everything they've posted
to YT, such as Playlists, Videos, Community chit-chats, etc...
Now, anything not created by this publisher, again LEGO, will not be on their
homepage.
Please Show Me More -  So, right below the video publisher's name and date of publication there is a video description. 

In this description field the publisher sometimes has links, or if
its a song, the song's written lyrics. Now, if the description field
gets too long and wordy, YT will cut it off after a certain length,
and hide the rest behind the "SHOW MORE" link.

So, try the SHOW MORE link to see if there's further info to
more official content.
YouTube Restricted Mode On/Off.  You can turn this on in YouTube settings to try to filter videos with potentially mature content, but note: Filters are not 100% accurate.   


Phone App - Restricted Mode On/Off


Open YouTube app.
Tap 3 dots in the top right of screen.
Look for gray "Gear Cog" to access "settings".
In settings, look for "Restricted Mode Filtering".
Choose either "Don't Filter" or "Strict". Done.








Desktop computer - Restricted Mode On/Off:


Click 3 gray "parallel lines" next to YouTube logo to open side
menu.
Scroll down/look for gray "Gear Cog" to access "settings".
Scroll down to the very bottom of page look for "Restricted Mode".
Click on it to access more of the page.
Scroll down some more. Toggle it "on" or "off".
Click "Save".
Done.