1. Before trying to sell the property, ensure that it does not go out of your hand, 2. The original deed may be deposited with an Bank for mortgaging the property for taking loan for which the Bank may sell it of as per SARFAESI Act,2002 if the loan is not paid, 3. So, first lode a police complaint against your brother for illegally keeping your original sale deed and refusing to return the same, 4. Release a press notification informing the general public about the loss of the original sale deed asking them not to deal with anybody for buying or mortgaging the said property, 5. After that collect certified copy of your title deed from local Registrar's office and conduct the sale.