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whats the difference between i could not ask for more and i would not ask for more?
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Anonymous i I would not ask for more.
1. I can't imagine myself asking for more (in that situation).
2. I refused to ask for more. / I was quite unwilling to ask for more.

3. I don't advise you to ask for more. / I don't think it would be right for you to ask for more.
Anonymous i I could not ask for more
1. I was physically unable to ask for more. (For example, something was caught in my throat. I was unable to speak.)

2. It was impossible for me to ask for more. (For example, the person I was speaking to left the room. Or, for example, there was no more available.)
3. (Idiomatic meaning) It was the best that it was possible to do for me. / I was treated very well indeed. / All my needs were completely fulfilled. / I was entirely satisfied with the situation.

CJ
Comments  
'I would not ask for more' gives the feeling that the speaker dares not to ask.

'I could not ask for more' means that the speaker couldn't ask because of some obstacle, even if he wanted to.
 CalifJim's reply was promoted to an answer.