Hi Asmaa,
Disclaimer: I'm having no luck on Upwork myself, as a translator, but these tips come from different resources.
I had a look at your profile, and I'd like to point out to you a couple of things:
First, I suggest you to translate only INTO your native language - that's what professional translators do, as translation and localization require a profound knowledge of the culture of the target country, the language alone is not enough in most cases -.
Second, try to state your fields of expertise, areas in which you have a strong knowledge (hint: even outside of translation, it doesn't necessarily have to do with that).
Third, may I ask you why do you say "[...] I'm only a translator [...]"? To possible clients, that might sound like you're underestimating said profession, it doesn't help at all, it doesn't really make them want to hire you, IMHO.
Fourth, why don't you take some tests to showcase your skills? I suggest you the English to Arabic translation test, as well as English language tests (hint: only show the ones where you get the best results, say, those with top 30% and above, hide the others until you can retake them and ge tbetter results).
Finally, I obviously don't know your approach when writing proposals, but you will find lots of resources on how to write effective ones around here, you should definitely have a look a those!
This is all I have to tell you, I hope you will find this information useful, and I wish you best of luck on and outside of Upwork!
Elia
