Any exercise that will fix this gap?

Any exercise that will fix this gap?

I have a gap like this on my hips/sides of my thighs or whatever you call that area. do any of you know any exercise useful for this? And what is those type of gaps called? i hate it and i really want to fix it.
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+1 y
By gap, i mean the concave area on the sides of upper thighs
Any exercise that will fix this gap?
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