For a translation task like this one you only need single words in their basic (uninflected) form.
This is best achieved with a good dictionary, and we have a list of online Latin dictionaries.
Google Translate and other such online translation tools are very unreliable; they will sometimes get it right, but they can also get it disastrously wrong.
You have three guesses, and you can now pick a dictionary of your choice and see what they mean.
(Even if you use a dictionary to translate from English to Latin, please always check the back-translations from Latin to English. There might be surprising nuances and connotations.)
- Curiositas is translated "desire of knowledge, curiosity, inquisitiveness".
Seems very appropriate.
- Compassio means "fellow-suffering, fellow-feeling", or maybe "sympathy".
This is not a bad choice either, but perhaps not as good fit as curiositas for "curiosity".
I recommend checking out words like clementia, benevolentia, misericordia and pietas.
To find a word that best matches your intention, take a look at these dictionary entries (and others you may find or others might suggest) and see which one seems most appropriate.
Respectus sui means respectus towards oneself.
(You had it in the ablative form respectu, but the nominative is more appropriate here. If you want a different case, then all your words should share that case.)
This word means "respect" in the sense of consideration, and it means literally "looking back".
I'm not sure which word would be a good translation for "respect".
If you are interested, you could ask a separate question about that point.
My best guess now is reverentia, but I suppose there are better options.
I would prefer to have a single word so that the three concepts look similar.
This would allow you to drop the sui.
How about dignitas?
It is finally up to you to choose which words seem most appropriate.
You can also take into consideration how the meanings and sounds of the three words work together.
For example, dignitas, pietas, curiositas might sound good.
Please let us know of your choice; I would be curious to know what you ended up with.
If you could do me a favour, tell your friend not to give a list of words to translate into Latin, but describe ideas that he wants to convey in Latin.
Words in different languages rarely have a one-to-one correspondence, but the same sentiment can be expressed in many languages.
