and operator on two metrics with one same label - promql

Question

in prometheus, I have two metrics like this:
metricA:

metrica{label1="value1",aa="aa",bb="bb"}

metricB:

metricb{label1="value1",cc="cc",dd="dd"}

I want to and these two metrics, but each time it shows No data.
How can I and these two metrics with just one same label

Answer 1

I found the answer in this doc
so the solution is:

metrica and on(label1) metrib