I had the same problem with my terrier and my germanlab . So, I changed the diet to a more fibrous and holistic food and every week during their baths I put on a latex glove and squeeze the gland by placing my thumb on one side of anus area and the middle finger on the other and squeeze in and upwards movement( this method is only to be done with the outside area only). My vet thought me how to do this and then it took some practice , you know like the first time you change a baby's diaper! anyways never had any problems after that!!