I've noticed in English that some words that are used informally to mean one thing don't necessarily have a one-to-one correspondence in the realm of precise legal writing. I would imagine the situation is similar for precise legal writing in Spanish as well. So I don't think you should assume that what you see in a legal context will exactly carry over to everyday speech.
Please do continue to take Google Translate with a grain of salt. I suggest you take a look at linguee.com when you want to get a quick panoramic view of equivalences between two languages.
The sphere of words that provide advice, instructions, requirements and reproaches is pretty large in both languages, with lots of overlap and opportunities for confusion and misunderstandings. Choice and interpretation involve weighing some subtle differences. When trying to translate in one direction or the other in this particular sphere, the following are particularly true:
(a) context is important; and
(b) certain patterns have been established, and pattern recognition allows us to communicate with a fairly good rate of success despite so much overlap.
I don't want to write a treatise on all the different permutations and meanings but I will try to give you a little taste, from the informal language world, not the legal world. I'll write a few illustrative sentences but keep in mind that on both sides, there is often more than one way of expressing the idea.
Manolito, ya sabes, debes quitarte las botas en la entrada y dejarlas en el tapete. | Manolito, you know you're supposed to take your boots off in the entrance and leave them on the mat.
Es tarde, debería acostarme ya, pero esta pregunta es interesante. | It's late, I should [OR ought to] go to bed, but this question is interesting.
De veras hay que llegar con máximo 15 minutos de retraso, si no, la doctora no los verá, son súper estrictos en este consultorio. | You really must [OR have to] arrive no more than 15 minutes late, because otherwise, the doctor won't see you. They're incredibly strict in this medical office.
Cuando empieza a hervir, tienes que bajar la lumbre. | When it starts to boil, you have to turn down the heat.
Note: this is a bit stronger than debes bajar la lumbre | you have to turn down the heat. Similarly, "Tengo que irme ya" is stronger than "Debo irme ya."
No me contestaron. ¿Debo llamar otra vez? | There was no answer. Should I try again?
Es imprescindible entregar algo antes de la medianoche, si no, saco cero en esta tarea. | It's imperative to hand something in by midnight; otherwise, I'll get a zero on this homework.
¿Forzosamente tienes que cortarte las uñas aquí? | Must you cut your fingernails in here?
Things can get more complicated, e.g. "debería haber incluido este ejemplo" and debías llamar.
If things get confusing, the following can be helpful:
Es recomendable que ...
Sería buena idea ...
(Note about legal language: As a parent with no legal training, one of my Office for Civil Rights education disability complaints failed because my son's 504 plan used the verb "should" instead of "must" or "will." I have never forgiven the investigators for failing to understand that the people who sit around the table writing the 504 plan are not lawyers.)