How to get output list in solidity funct i have a struct of Drug and a table named drugs of Drug i need to get a list table of drugs having same name

Question

I try this but it doesn't work! any suggestions please ? 
    function getdrugs(string memory _name) public view returns (Drug[] memory) {

  Drug memory D;
        for(uint i=0;i<counter;i++){
            if (keccak256(abi.encodePacked((drugs[i].name))) == keccak256(abi.encodePacked((_name)))){

            D.push(drugs[i]);
                return D;
       }}}