You are using Incognito search mode while browsing which is safe but the websites are still looking at your browsing history without your acknowledgment. So to delete your Incognito search history on your Android phone using Chrome, type the mentioned URL chrome://net-internals/#dns Google Chrome address bar. At the left panel, select DNS by clicking on it, then tap on the Clear host cache button which will clear all the DNS data and also delete your Incognito history.