Here are my thoughts...
Milega Cocktail ka Tadka
This is for us audience - The upcoming track is going to be a balance of emotion, drama, happiness, romance
Padega phir se Dushman ka phatka
Gayenge hum ' Hogi Pyar ki Jeet'
Here the Dushman is Daadi because only she gives phatka and when it comes her phatka her target is Khushi so Khushi is going to get a dressing down and we already have the promo to confirm that.
But this dressing down will again witness Arnav supporting Khushi and taking on Daadi to protect his wife. So their love will come out victorious
Khelega kio 'Dil Se' hide and seek
This could just mean Arnav and Khushi will complete the wedding rituals privately in secret because they don't want the family to know about their contract marriage yet want to complete all the rituals that were left incomplete.
This could also mean' Anjali will continue to play hide and seek with her family keeping in touch and meeting her secret visitor without anyone's knowledge.
Sazegi 'Suhaag' ki sez
For Arnav and Khushi and a possibility of them having or at least trying to have an intimate moment.
Bardega aasuyo ki barish 'Tezz'
Not sure whom is this is referring to but there are going to be some teary moments' maybe Khushi or Anjali
Manayege hum toyhar 'Haste Haste"
This is for janmanstami festival which will be celebrated in happiness
Sab Kuch hota rahega 'Chupke Chupke'
This is for Anjali and her secret meeting that will continue and whatever is cooking will continue away from everyone's preying eyes.
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