I am attempting to do use the BLAST web server for finding nucleotides which contain both of two query genes. I attempted to do a BLAST using the accession numbers of both genes separated with the logical operator AND. However, this lead to an error message. My second thought was to do a BLAST with one query gene, then followed by a second BLAST of these results using the second query gene. Is there someway I can either BLAST for the presence of both genes in nucleotides directly, or a way to do a BLAST of a previous BLAST result using the web server?