Step 1: Identify the concept.
This is an example of **complementary goods**. Complementary goods are goods that are consumed together, such as tea, sugar, and milk.
Step 2: Explanation.
When a consumer demands two or more products together to satisfy a single want, they are called complementary goods.
Step 3: Conclude.
Therefore, Amar's demand for milk, sugar, and tea powder is an example of complementary goods to satisfy his want for tea.
Final Answer: \[ \boxed{Complementary \; Goods} \]