"Ellos tienen libros."
Translation:They have books.
Possibly you do with the initial 't'.
Sometimes, it sounds like people are saying a 'd' instead of a 't'. It depends on where they push their tongue off from their top front teeth.
Closer inside the mouth or closer to teeth. I notice this difference between different regions across southern Spanish speakers, some Americas and some Arabic consonants. Especially when I hear the man in these Spanish lessons.