Currently we are doing 'no-cry' method to sooth her to sleep.
I've not heard of this technique...could you describe it to me?
So, looking at her routine, I think she's caught in an undertired/overtired cycle. At 4mo, most babies are staying awake for ~2h and taking naps ~1.5-2h in length. Her first nap is on the short side, and I think that's where the day is veering off track. She's not tired enough to take a LONG nap, and then she can't do a full A time on a 1h nap so the rest of the day gets overtired/fussy/hard to settle.
Try bumping up her first A time by 10-15 minutes every couple of days until she starts taking a longer nap. When she does take a short nap, that following A time needs to be reduced by ~15-30 minutes so that the next nap isn't OT.
my concern is she's developed a habit to drink before bed... it seems like she's grumpy after bath because mostly she's sleepy and wants to drink milk. so when she takes the 7:00pm feeding, she falls asleep right away.
Considering that her last nap is only 1h long and she's pulling a really long A time before bed on top of that, I can understand that she's very sleepy by the end of the day. Her bottle is her way of coping with the tiredness. It's completely okay to give a bottle right before bedtime...just as long as it's actually feeding her to sleep. If you see she's falling asleep on the bottle, either stir her a bit to wake her up or just put her to bed and feed again at the dreamfeed.
Does that answer your questions?