Tayuya manipulates her three Doki with the sound of her flute. Her melody releases materialised spirits, which are actually special chakra sealed inside of the Doki. The materialised spirits are composed almost entirely of spiritual energy, so the chakra is in an unstable state. Therefore, they crave physical energy, so they hunt for their prey endlessly.
Shikamaru noted in his fight with Tayuya that her techniques use special chakra and she must be a user of hiden techniques, just like Shikamaru himself. However, the second databook doesn't label Tayuya's techniques as hiden.