Can I use cellphones bought from china?
I'm thinking about buying the lenovo s700 or the DOOV s600.
Do you know if I can still use them in the U.S?
If not, do you have any recommandations on pretty white flip phones that i can use there in the U.S?

Yes But check for IMEI no by pressing *#06#
Of course you can, if your local cellphone service is GSM, not CDMA. And be careful that whether the SIM card in China is the same as in US.