I have a problem while reciting Ayn; I end up reciting from nose specially when there is sakeen or dhamma?

As salaamu alaykum

I have a problem while reciting Ayn ... i end up reciting from nose specially when there is sakeen or dhamma on Ayn it comes way too much from nose... Can you please give some tips to correct my self...

Jazakallah Khairan

Wa alaikum assalaam wa rahmatullahi wa barakatuh,
This not too uncommon.  The usual cause is a weak articulation point, or the lack of using the correct articulation point, and the sound then ends up in the nose. 
The first step to correct it is to practice saying the letter  saakinah with a hamzah with fathah before alternatively with the saakinah. The two letters should be said rapidly one after another many times and the reader should concentrate on the area of the throat being used.  These two letters share the same articulation point, so saying the first, assuming it is correct, then the should keep you focused on the correct articulation point. 
The second step once this is mastered is to try and use the same method for the with the different vowels, plugging your nose as you do it to make sure the sound is not coming out your nose.  It will be quite apparent if it is.  Try to focus the sound out your mouth.  You can practice with the alternatively with the again if you hear the sound coming our your nose when you have the nostrils closed off. 
Always start your practice with step one, then move on to the voweled once you have the saakin letter perfected. 
It may take a bit of practice and patience to correct it, but insha' Allah you will be able to do so.  Remember to make dua' asking Allah to give you the correct pronunication of all the Arabic letters. 
May Allah perfect your pronunciation in all the Qur'an.
Wa iyyaakum.