Your plants look pretty tall and lanky. They appear to have a lack of sunlight so they are stretching for more of it. The culprit is most likely the light you are using. You are only providing light to the top of the plant when it is inside, whereas the plant can utilize light on every side and leaf.
I recommend getting some more light in there, and reiterating to me what type of light you are using so we can point you in the right direction.
Alternatively, if you transplant them, take them outside and leave them there you will notice the plant start to become more compact and bushy, an ideal quality for vegetative growth and increased bud production in flowering.
The plants can utilize a ton of light, so the best thing to do is provide them with it.
Hope this helps.