I know I filed a bug about this before.

https://musicbrainz.org/search?query=big+bang&type=artist&method=indexed
Okay, no quotation marks.

https://musicbrainz.org/search?query=%22big+bang%22&type=artist&method=indexed
"big bang" with quotation marks results in the same order of results (with +/- 1~2 relevancy). "Big City Gang Bang Productions" (https://musicbrainz.org/artist/aae4c508-b3c5-4547-90de-c116846057c3/aliases) before an artist with search hint "big bang" (https://musicbrainz.org/artist/ec2bcb77-b9a1-49e2-bfe7-419586bbef48/aliases)

https://musicbrainz.org/search?query=big+bang&type=artist&method=direct
No quotation marks. BIGBANG comes up in the first 25 results now. "Big City Gang Bang Productions" now comes up as the dead last result (0 relevancy).

Expected behavior:
a) An artist with search hint "Big Bang" will show up with the same relevancy as an artist named "Big Bang".
b) The more extra words in an artist's name, the lower the relevancy when searching for part of the artist name. (i.e., "big bang" should yield "Big Bang" before yielding "Big City Gang Bang...")