Thanks for your help, i couldnt come back before.
I dont know what is "tracker reset"...so probably nothing has been done.

I installed n9 qtweak all restored and found the 2 sms...
Then since this moment my girlfriend (even with a lot of reboot) have only her new sms, the old ones all lost....

I should try to copy on my computer the /home/user/.cache/tracker/meta.db ?

Thanks a lot for your help. In fact it would be nice to be able to have like on computers a restore tool of erased data