They look like a common LIPD pair that one of our local retailers (jaycar) sell.
They're simple OOK. The first thing is to verify that your TXer is working properly.
You can do this if you have a scanner, tuning it around 434MHz, usually about 434.900MHz and listening for the carrier and any data you might be sending.
You should be sending less than 9600bps because these modules are hard pressed to work even that fast.
If this is ok, then transmitting a carrier only will cause the RX module to activate on it's output line.
Using a 555 timer with 1Hz pulses and an LED on the RX data output to test the receiver.
https://www.electro-tech-online.com/custompdfs/2012/05/ZW3102mod.pdf
The only other thing that stands out is the voltage levels. They might not be TTL levels or whatever you're using.