In the second book of the Yoga Sutras, sutra no. 44 it says:
“By study of spiritual books comes communion with one’s chosen deity”
Svadhyaya then means spiritual study and one refers to the study of what can be called holy scriptures. As yoga has come to the West by storm, much of the wisdom has been interpreted and reformulated by people without competence or understanding. By searching on google and studying there, you will therefore most likely end up on the wrong track. When studying spiritual texts, it is essential to look at the source of the information.
Svadhyaya does not only mean to study texts, but also to perform your sadhana (Spiritual practice) in which you have been initiated in. Regular practice becomes study. By doing so we get the ‘ista devata samprayogah’ – the vision, or darshan of God.