This is because we search for some words in the browser, such as learning to worry about the diameter symbol after the search, there will be a diameter symbol of the cache, so if someone in the input diameter symbol will be in the Drop-down search box to see that we have to find the key word diameter symbol. As shown in the figure:
Of course, here is a relatively simple way to move the mouse in the diameter symbol above the word, in the following will appear an X symbol, click the x symbol to delete this search term record cache.
Another way to do this is to teach you to clear the cache without others discovering your search record. First open Google Browser, and then use the mouse to click on the top right of the browser "wrench" icon, pop-up drop-down box select "Option", you can open the Google Browser Options window.
After pop-up Google Browser Options window, click "Clear Browser Data", in the following options in the "Clear browser history" and "empty the cache" and the history of all tick-checked, check after the click OK.
The latest version of Google's browser interface can have some changes, but also click on Google's browser a "custom button-tools-clear browsing record", as shown in the picture:
This way you re searching the keyword for the diameter symbol on your Google browser's search box so that the record does not appear. As shown in the figure: