Before you finalise a mark for your business or product, the applicant must first ensure that no one else is using a similar mark.
A search is done to validate the following criteria for a brand name
Say you want to register Google as a brand name, you will first check if another Trademark with the same name has been registered. If it is registered, you can avoid a lot of trouble by selecting a different brand name or logo.
If not, you should.
Trademark registration for identical mark is possible if the goods and services are unrelated.
For instance 'Apple' is registered trademark for mobile and devices that fall in class 9 and is registered by Apple Inc. Body Incorporate, but there exist identical trademark that is registered in class 25.
When conducting a trademark, you should always look not only for identical but also for similar marks that might look alike or sound alike.
To illustrate, Sardarbaksh Coffee & Co. a famous cafe faced heat from Delhi High Court, that has asked them to change the brand name which is phonetically similar to Starbucks.
The purpose of a search is to simply unearth marks that are similar in any way and hence you are advised to check marks with similar prefix and suffix.
As can be seen, when searching for word 'Apple', the search should consider derivatives like Applee, Applefun, Appletree and applestree.
Anyone can search trademark for free using Quick Company's Trademark Search tool; this page shows all the Trademark Applications filed in India. Alternatively, the same search can be performed on the IP India's website.
If you are registering a mark that was previously abandoned, you are advised to check the reason for the abandonment of the application.