There are topics, where the available official documentation is not great or is hard to search for, so you are thankful for every little piece of the puzzle and you need to search with broad terms.
If I get different types of content in the result list, usually I check first the documents (there are a few really good ones), then the blogs, then the wiki (most pages provide very few details, but you might find there some useful SAP notes) and then I check the discussions (most time-consuming, but quite often helpful).
For discussions and blogs: currently I try to filter by space and date range, and I usually need information from several spaces. Unfortunately the existing SCN search in find.sap.com has a limitation on the number of spaces that can be shown, so sometimes I have to drill down a bit to find the relevant ones. The other annoying part is that there is no option to select 2-3 spaces as a filter criteria - e.g. ABAP Development + SAP SD + S/4 HANA + SD Billing.
Translated to the new tag concept: let's assume that I get update terminations when posting a billing document in S/4. After reading some SAP notes, I will search in SCN for content tagged SAP SD, SD Billing, S/4 HANA, ABAP Development - primary and secondary, but I really wish to filter out from the result list anything tagged Business Trends as primary and secondary tag (I mean no disrespect, but if I have a real problem to solve, I won't have time to read this type of content). Then I might filter by dates (because of HANA) if I get more than 300 hits.
Language selection: this can be tricky. What if I don't go to the SAP homepage, but use a direct link to SCN? What if I am on a business trip to a country, where I don't speak the official language (Portugal for example)? What if I connect via VPN to my corporate network and the server is located in Austria, but I speak only Russian? There is a way to set languages in our profiles, can't we use something like that to select results in which language to appear in the search? If you are not logged on, then show all and provide filters by language in the lists.