曶 is a Chinese hanzi, listed here under the keyword “used in personal names”. It is built from 勿 (must not) and 曰 (say). It appears as a component in 1 other character in this index.
On KumiJi Glyph Explorer, open the parts search and type “must not” + “say”. 曶 is among the results, together with every other character containing the same shapes.
Open 曶 in the interactive kanji search
to expand every part down to its smallest pieces, add your own names and mnemonic stories,
or search for other characters by their parts.