how to put two different back up sync dates together on Iphone?

[ibcrazy23]

i got a backup sync dated dec.25 and another one dated march 14 and i was wondering how i could synce them together...or i wanted to get my text messages from both backup dates and put them together is there a way how doesnt matter if it is alot of work...i just really want those text messages with my new text messages bc i accidentally deleted it before i back it up on march 14....please some help me