Censys expands queries to provide additional functionality. For example, the query a:zmap.io
executes a DNS lookup and expands to ip:141.212.120.90.
Your query was changed from:
parsed.tbs_noct_fingerprint: ef14ea05bb066ee9f4188196dd69cd769b283ac4d7555db52f5e76922d3456e1 and precert: true
to
parsed.tbs_noct_fingerprint: ef14ea05bb066ee9f4188196dd69cd769b283ac4d7555db52f5e76922d3456e1 AND precert: true
If this isn't what you intended, you can run your raw query without expansion.