“ไม่เอา” is usually used when you want to refuse an offer or to say that you do not want something. However, if you add the particle “น่า”, of which the tone generally changes from falling [nâa] to low [nàa] when spoken, at the end of the phrase, it means something along the lines of “Come on! this is not a good idea”. It is used to persuade or slightly beg someone to stop doing what he is doing or to give up of his intention to do something. For example, if your friend urges you to sing in front of everyone, you might want to say “ไม่เอาน่า” [mâi ao nàa]. Or if your friend talks about his plan to revenge someone and you want to discourage his idea, you can also use this expression as well. Another example, if your friend regrets leaving his girlfriend and is mad at himself, you can try to encourage him to stop stressing over his mistake by saying “ไม่เอาน่า อย่าเครียดไปเลย” [mâi ao nàa, yàa krîad pai loei].