1.It is to be seen whether there is any indemnity clasue in the sale deed.
2.Generally such clause remains in the sale deed and if it is there Raju is bound to compensate the buyer.
3.If there was fraud on the part of Raju in selling the land then the case of cheating can be filed.
4.Do Note that each and every dispute which Raju may have with his relatives is not enough to file case of cheating. His relatives may have some dispute which has no legal basis for which raju wouldn't be held responsible.