I have an exceptional music box. I can put words inside it. But not all. Here are some of what this curious box admits:
- Relation
- Abomination
- Sofa
- Umbrella
- Antidote
- Gasoline
- Desire
Can you deduce which words my box admits?

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Sign up to join this communityI think your box likes
words that contain tonic sol-fa syllables.
Thus:
relation
abomination
sofa
umbrella
antidote
gasoline (I think you could also count "li", as a sharpened "la")
desire
This has already been answered but I found another answer that fits all the provided words.
Your box admits
Words that contain other words inside them
So we get
Relation
Abomination
Sofa (or Sofa)
Umbrella
Antidote
Gasoline
Desire