Rescue dog owner here. What I learned in the process of trying to raise a dog who was and in "difficult" situations still is very shy, unsecure and easily scared is: Before starting to communicate (whatever it is, verbally commands, gestures, body language..) take a second to feel your own mood and if neccessary -> adjust it if you can.
Dogs are very good in reading your voice, interpreting your body language, so
when you are in hectic, stressed, pissed, annoyed it really makes a difference to take a breath and cool down, a really short second is enough, the message that your dog will receive is a total different. Its so crazy. Same goes for body language, too. Your dog doesn't come when you call? Try to make your physical appearance smaller, turn 90°, make an inviting gesture and take little and sloooow steps backwards, higher your voice, smile, be positive and see what happens. Since I understand the importance of my own vibe in every dog communication life is easier, so much easier.
Dogs are very good in reading your voice, interpreting your body language, so
when you are in hectic, stressed, pissed, annoyed it really makes a difference to take a breath and cool down, a really short second is enough, the message that your dog will receive is a total different. Its so crazy. Same goes for body language, too. Your dog doesn't come when you call? Try to make your physical appearance smaller, turn 90°, make an inviting gesture and take little and sloooow steps backwards, higher your voice, smile, be positive and see what happens. Since I understand the importance of my own vibe in every dog communication life is easier, so much easier.