Web of knowledge is a group of databases offered by Thomson ISI. You can access Web of Knowledge from the library's web site under the "Databases and Electronic Resources" tab. Here is the direct link: Web of Knowledge.
You will be asked to enter your unikey login and password in order to access the database as it is not freely available on the web. More information about accessing library eResources like Web of Knowledge can be found here: https://library.sydney.edu.au/databases/access-eresources-and-help.html