Censys expands queries to provide additional functionality. For example, the query a:zmap.io
executes a DNS lookup and expands to ip:126.96.36.199.
Your query was changed from:
parsed.tbs_noct_fingerprint: 9a88031d42e57415616d89439149e254adb7a9a653ea90f4ac5100bb496eaef0 and precert: true
parsed.tbs_noct_fingerprint: 9a88031d42e57415616d89439149e254adb7a9a653ea90f4ac5100bb496eaef0 AND precert: true
If this isn't what you intended, you can run your raw query without expansion.