`if there are only 28 address lines and each carries one bit how there can be any more data?`  
I don't read *28 address lines **all told***, but *28 address lines going into one specific memory device*.  

`where are the 4 address lines to carry [the 4 bits out of 32 that are used to activate the memory device]?`  
There are two answers on the conceptual level:  
- A> Those are the most significant bits  
- 1> As long as the "gaps" in the address space that are *not* handled by the device is not addressed by *contiguous least significant bits* are handled properly, it doesn't matter.  
For details on why and how this may be done purposefully, read up on *memory controllers* and [interleaved memory](https://en.m.wikipedia.org/wiki/Interleaved_memory).