If a female has a manly voice, is there any therapy to get female voice?

If your voice is naturally deeper than you would prefer, please know that it is determined by the length of your vocal cords. There is no way to shorten them, so you might want to work what you have to make it as beautiful as you can if you are tired of consciously affecting a higher pitch when speaking. Search for speaking and singing tips online. Perhaps you can gain better control of your voice to make it more melodic which is often complimented as an attractive quality in a speaking voice.

The voice can be controlled to give many different sounds. Courses in drama, public speaking, or story telling are tailored to develop those controls.