Switching a relay from its supply (2 Relay Module, VCC to IN1, doesn't work)
The module you are using needs the inputs to be pulled to 0V (ground) in order to switch the relay.

Check the manufacturers webpage for the module: 

https://www.sainsmart.com/sainsmart-2-channel-5v-relay-module-for-arduino-raspberry-pi.html

This has a picture of the input circuitry on the module, which uses an optocoupler:



You need to redesign the rest of your circuit to take account of the fact that the inputs take negative logic:

INput: Low, Relay ON
INput: Vcc or floating, Relay OFF