How to improve video ranking in youtube search?

Try to long tail keyword for your video tittle and write useful and long description about 500 words about your video and video info. Always use related tags and try to use more tags and share social media and forums. 
create internal and external video link. Create some playlist and get more view and subscriber. Hope you get better rank on YouTube.

Make sure to share the track with your subs, include any and all tags somehow related to the track itself (basically think that if you forgot that vid you did, what tags would you put in to help you find it? was it emotional? put in "emotional". Did it have an anime character in the background? include their name.), like/favorite it as it will put it into the the activity feed, be sure to respond to the comments as they come in as it will also put it into the activity feed and share on social media as exposure brings in views which creates more activity. Do this enough times and your vids will begin to show more prominence in the youtube feeds