I write my new item’s name to the search field but it doesn’t appears in results. I choose “best match” again but there are lots of items has another titles. I can’t understand reason of this.
Calling your item “Upbeat” is going to have your item compete with a lot of other items. There are a lot of variables involved with search, brand new items meeting a search term do not necessarily go to the top of the list. When the search results are sorted by “Added in the last day”, your item is third in the list so be assured that your item is part of the results. 
It’s ok. Thank you mate 