"On the other hand, for the sport centers which their demands are slightly over, the government could lift their capacity by upgrading their facilities"
Could "which" be substituted by "where" or "in which" in the sentence?
On the other hand, for/regarding the sports centres whose demands are slightly higher, the government could increase their capacity by upgrading their facilities.
Is that close to what you meant? I have assumed that the demands are demands for more seats.
Remember - correct capitalisation, punctuation and spacing make posts much easier to read.