The abbreviation "sth" occurs here a lot, probably because of people who learned...

hollerith on June 8, 2019 | parent | context | favorite | on: Absolute truths I unlearned as junior developer

The abbreviation "sth" occurs here a lot, probably because of people who learned English with the help of dictionaries that use "sth" as an abbreviation for "something". I suspect "sbd" also comes from the same source.