Navigation genre/Tag function not working

Hello, 

Apologies if you are already aware, but I’ve noticed for the past two week the search function isn’t bringing up all the results for each tag and genre. For example if you search for upcoming fantasy dramas it doesn’t return all of the dramas marked by that genre or tag, but only a few. Specifically it’s missing a number of dramas that have been tagged as such and can be searched by name, but not as a group under one genre/tag. 

Hope that makes sense?

Are you able to look at this thank you?