hale
There was one word that would fit the meaning of indentation and desperation. This word would be 'rash' and also fits the four letter length.
'Slit' would fit.
'Rake' might fit, or 'scum'.
Scam would fit this definition.
fit
A four-letter word for a sewing kit is "sew." However, if you're looking for a specific item within a sewing kit, "need" (as in needle) could also fit, but it's not directly synonymous with a sewing kit itself. The term "kit" can refer to the complete set of tools used for sewing, but it does not have a commonly recognized four-letter synonym.
fit, apt
Only 'pooh' seems to fit.
Regal
The word teeth would fit the description.
There are two words that fit your search....Dune or Wash.
Users seems to fit.