New Stream search results are poorer than classic search results

[Tamir Levy]

I would like to know why when search the same word without any filter give different results between the modern and the classic stream?

in my example when I search for "Viva" , the classic results returns a lot of items I can't find in the modern results. 

why is that and why would I want to use the new stream in that case?

[#2]

That box you typed in from stream office.com experience is a filter on your recent or recently shared with you video files.it filters down the of videos shown. This is how all of office.com works for word, PowerPoint, excel. If you search at the box at the top it'll do a full m365 search across all files in your organization. We are working on making that search box at the top filter down to videos by default.

The m365 search is much better than Stream (Classic). It supports real search queries, filters, and actual relevance.