Type-ahead realize two-level fuzzy searching

Problem: 

1. Create a new memo 

2. In TO field, using type-ahead can searching the similar user name,  but it is only fuzzy search user name.

3. There are many persons of the similar name, but different department and location exist in company. 

For example:

There are 100 person, from Li ping1 to Li ping100, sender doesn't know the recipient is Li pingX, but he know his department or location.  So when he input Li ping in TO field, the fuzzy searching list 100 users, it is too long to select the correct one. 

So exception: 

Type-ahead can do two-level searching to locate to department or location, like check OU via button or others.