How to recover my contacts I accidentally deleted all my contacts from my phone. In my Google Contacts I was able to recover some of my contacts but how or where can I find the rest of my contacts?
If, you haven’t wiped your device completely, there is still a chance of recovering your lost or deleted contacts by checking if the old contacts database file is stored somewhere deep in your storage.

Depending on your manufacturer and Android version, you will find your database in different locations in your storage. For stock Android devices like the Nexus 5, the database file should be located here:

/data/data/android.providers.contacts/databases
The key that your are looking for is providers.contacts/databases. To get to this folder straight from your device, install aSQLiteManager, which is able to get into your Android device’s database storage and open .db files.

If you can find this folder on your device and it’s empty, it means that your contacts are gone for good.

Well… Now it’s time to blast out a message to all your friends on Facebook, Twitter followers, business contacts and your family, asking them to send you their contact details.
credit(Daniel) 
also check this link