I want to use some of the Persian words and want to write in in English Noun phrases like the following:
Majid Ketabkhane Management System
where Majid is an Arabic name and Ketabkhane is a Persian word meaning library.
So am I allowed to use this phrase in this form as trade mark for a software?
You can name your system anything you want; the real question here is, do you want your customers/userbase/readers to understand what you're talking about from the name of the system? Because as it stands, no one will.
Majid Ketabkhane Management System
An English speaker is going to have no idea what that is. Okay, it's a management system of some sort. But what does it do? I have no clue; I haven't been given enough information to figure it out. So if I get an email about your system, or see an article about it on the web, I'm not going to be interested (unless the odd name jumps out at me and I click merely for the sake of curiosity.) More importantly, your target audience is presumably people interested in libraries, and they have no way of knowing that your system could be useful for them. So giving your system this name isn't a practical attention-grabber.
Now let's make one change and see what that does. Since you've told us that ketabkhane means library, let's do this instead:
Majid Library Management System
This makes a world of difference in how your system name will be understood and received. I know so much more now; it's not just an unknown "management system" of some sort; it's a library management tool. It doesn't matter what Majid means; I'm just going to assume that's the name of the library management system (which is something I can understand). Consider these:
Majid Donut Shop
Majid Word Processor
Majid Smart Phone
In none of these cases does it matter to me what Majid means; if I know I'm dealing with a donut shop or a library management system, the name of it doesn't matter much. So if you stick with Majid Library Management System you're going to get the attention of people who work in libraries and who your system is presumably targeted at. And I think this would work out nicely!
English is well known for "adopting" (some might say stealing!) foreign words, so I'd say this is fine. Bear in mind that the pronunciation and spelling are highly likely to be mangled by natives no matter how hard you try!
You can name things whatever you want in most countries, as long as the name is not offensive. I'm not sure if that is what you are asking, though.
It depends on what you are trying to accomplish. As a Trademark yes. But if your looking at something more as comprehensible you would need to take the word Ketabkhane and translate it as library unless that word has extra meaning that isn't in English. For example raw fish is not the same as Sushi. They roughly translate the same, but that's because we don't have a food in English that's like Sushi. So in the case of Sushi it is more than just raw fish and a direct translation doesn't really work. In this case English adopts the word and the meaning completely. Sushi becomes (or shared) an English word. Really I think Sushi is an international word.
Standard usage in the US is to put foreign words in italics--especially if they are unfamiliar to your readers. Otherwise there is no problem with using them.
MajidandKetabkhaneare not offensive and have the same meaning posted by the OP.