I'm new in Ethereum and I have a smart-contract that receive exchange rate from API through oraclize. But I have problems with testing my smart-contract. For testing I use truffle + ganache. Could anybody give me some examples or advice how to do this?! Thanks in advance!!!
Try Oraclize's fork of remix: http://dapps.oraclize.it/browser-solidity/#version=soljson-v0.4.20+commit.3155dd80.js
It's a much simpler IDE, and is great for prototyping. It avoids the steep learning curve that may come with truffle + ganache (although for production you will definitely want to use something like that). To go with truffle + ganache, you'll need to use Oraclize's ethereum-bridge to deploy the appropriate architecture to your private network.
Here's a whole bunch of Oraclize example contracts. All should work right in the browser VM of the initially mentioned IDE (except Random DS, only available on public networks). https://github.com/oraclize/ethereum-examples/tree/master/solidity