To get more information about Topic Specific Collocations and how to use them, follow up on these websites:

• English Club – Collocations
• The BBC – 109 Common Collocations (PDF Download)

For an interesting way to gain academic vocabulary, try these radio shows:

• Radiolab – Science focused radio show (American English)
• No Such Thing As A Fish – Facts based radio show (British English)

Here is a whole podcast dedicated to these techniques and more IELTS vocabulary, which also includes a great resource for learning Topic Specific Vocabulary – great if you are aiming for a Band 7/8 or 9.