Questions & Answers about Kad govori istinu, njen pogled je miran.
Kad means when here. It introduces a time clause: Kad govori istinu = When she tells/speaks the truth.
In Croatian, kad and kada both mean when. Kad is just the shorter, very common form.
Both can work, but they are slightly different in feel.
- govoriti istinu = to speak/tell the truth, often in a more general or ongoing sense
- reći/kaže istinu = to say the truth / tell the truth, often referring to a specific statement
Because govori is imperfective, it fits well with a general condition or repeated situation: When she tells the truth, her expression is calm.