Dictionaries designed for speakers of a specific Chinese language
might organize its entries by pronunciation
(this makes the dictionary useless for people that speak a different Chinese language),
Some dictionaries might organize its entries by some kind of code,
for example Changjei code (a system used by professional typists) or the 4-corner code.
Which is perfectly possible, because
咗 contains a stroke that looks like an upside-down L,
which looks like two lines but
counts as one.