I too have thin hair that's been colored (blonde in some parts). My hair stylist's brand in Paul Mitchell so of course they are always trying to sell me that, and for a very long time I wouldn't purchase any of their shampoos because I felt they were overpriced. However, once I got my hair ombre'd I decided I'd buy some Paul Mitchell shampoos from Sally's opposed to my salon, since it's quite a lot cheaper there. I picked up their Tea Tree brand which has some good, natural oils in it, and I used this for a while. I realized (because I was sort of clueless as to what works with my hair) that I needed to alternate between more shampoos since I got my hair treated, ones specially formulated for treated hair. I called my hair stylist up and she recommended the Super Strong Daily Shampoo & Conditioner by Paul Mitchell, as well as Shampoo Two by Paul Mitchell. My hair isn't as flaky and dry at the roots as it used to be and I rarely EVER get build up anymore. I noticed my ends seemed kind of dead, which concerned me because I hadn't applied heat or any products to it, so I switched up my routine a bit and purchased Aussie Three-Minute Miracle conditioner, which has literally done wonders for the ends of my hair, it makes it feel silky and gives off a nice shine, and TA-DA my ends were way less dry since the conditioner was the nourishing boost my hair desperately needed. Before I got the highlights in my hair I used Mane & Tail Shampoo & Conditioner as well as Nioxin, which I actually believe may have thickened my hair up significantly, but since the highlights I haven't gone back to these original products just because the routine I'm doing now has worked very well. I hope this helps, I'm no expert but I can definitely relate to your hair type!