You can use several words in query to find by all of them at the same time. In addition, if you are lucky search understands word forms and some synonyms. It supports search by title and author. Examples:
305 — search for 305, most probably it will find blogs about the Round 305
andrew stankevich contests — search for words "andrew", "stankevich" and "contests" at the same time
user:mikemirzayanov title:testlib — search containing "testlib" in title by MikeMirzayanov
"vk cup" — use quotes to find phrase as is
title:educational — search in title
Yes, I think it is better to search blogs with the same tags.
Auto comment: topic has been updated by VuNamDuong_dt8 (previous revision, new revision, compare).