I encountered two characters I cannot find in any database. They are side-by-side compositions of two characters that I do know, but I have not been able to use the information to find something I can copy and paste into text. I tried radical + stroke look up for the characters at https://www.mdbg.net/chinese/dictionary?cdqrad=184 and https://www.mdbg.net/chinese/dictionary?cdqrad=107 using the components as a clue and even drawing them directly into a a handwriting keyboard.
The characters below are shown with their probable homophones. (I found it in Yuen Ren Chao's A Project for General Chinese.) So I also tried looking up the Mandarin and Cantonese pronunciations on Unihan database with no luck. They are not found together on Wiktionary's lists of phonetic series either.
瞞 and ⿰食㒼
脫 and ⿰兌皮