Do you mean limp looking strands, as in a little dirty looking? Or are you referring to thinness? I've noticed that recently my hair is looking really stringy and I think it's from over oiling. If you use oil, try limiting the amount...
I've also noticed my hair became stringy ever since I switched to non-sls shampoo, hopefully it'll adjust and get bouncier. I think build-up could be another cause for 'stringiness' so one solution is clarifying once in a while.
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