Translation - Turkish-English - Aşık olamayan adem, yemişsiz ağaca benzer.

Weird sentence, isn't it?

In order to sound better in English...could we change it into:

"A human being (or Someone) who never falls in love is like a tree which never bears fruit."?

Will that still convey the original?

Yes, it might be. But what's weird about saying 'a tree without fruit'?

I think it's not the same "a tree without fruit" (it may have already beared fruit someday and now there isn't any on it)) from "a tree which never bears fruit"

See what I mean?
I think that way the second part of the sentence fits the first part better. I may be wrong, please correct me.

I see, thanks. On my second reading, I realized there is a letter in the original sentence that escapes my notice, which makes the sentence into:

A human being who can't fall in love is like a tree without fruit.

Is that OK with you?

I'd put it this way:
'A human being who can't fall in love is like a tree which can't bear fruit.'

Same thing goes for that. OK, then, I'll edit it as you said. Thanks a lot.