Analysis popular titles, gain the recommendation from YouTube search
Die 5 unglaublichsten Serienkiller aller Zeiten
It's great. It's a perfect length for titles.
Fewer keywords, and increasing the number of keywords can help you get the search recommendations
Great, well-defined titles that help increase CTR
Separate the title into 2 to 3 parts
Normal performance, using - or | delimited symbols helps search for recommendations