When you go to www.google.co.in where you generally search for everything in English, Google also offers the search to be done on regional languages like Hindi, Bengali, Telugu, Marathi, Tamil, Gujarati Kannada, Malayalam, and Punjabi. As I am much familiar with Tamil I will show you how to use Tamil keywords to do a search.
1. Go to www.google.co.in, you can see the list of above said languages (shown in the screenshot below)
2. Click “Tamil” and you will get the same search page in Tamil shown below,
3. When you are not familiar using the keyboard to type Tamil letters (like me) just try out something, for example to search for the keyword “Amma” (means Mother in English) type “amm” you will get the keywords in the dropdown shown below,
4. Google also offers a Tamil phonetic keyboard, you can see this from the screenshot shown below,
5. When you click this (highlighted in the above screenshot) you will get the keyboard in English, press “Alt+Ctrl” button to get the letters in Tamil.
6. Now just select the Tamil letters which will appear on the search text box. (every time you press a Tamil letter from this keyboard the letters change to English, so press “Alt+Ctrl” button again)
Also check out tips to use Google search