Quantitative structure-property relationship modelling for predicting retention indices of essential oils based on an improved horse herd optimization algorithm by Alharthi, Aiedh Mrisi, Kadir, Dler Hussein, Al-Fakih, Abdo Mohammed, Algamal, Zakariya Y., Al-Thanoon, Niam Abdulmunim, Khalid Qasim, Maimoonah