What colors could I use to achieve these?

In the second pic the top colour could be Directions Cerise, I'm not sure about the bottom, an apricot colour, maybe diluted  orange?,  the first picture looks like these colours but in a pastel form or dye diluted with conditioner.

Maybe you could look through the gallery and see what others have used to achieve similar colours, results can very according to your natural shade as well. Good Luck!

The first one to me looks like diluted carnation pink over slightly darker blonde hair (which is giving it the corally tone). If your hair is purple you'll need to get all of that out before trying for a warm toned pink like this because the blue in purple will pull it towards a cool pink.