You can do a tire search by choosing any and/or all of the fields shown in the drop down menus. You DO NOT have to choose ALL of the fields. You can skip any fields that do not apply to your tire search.
(EX: If you are looking for a 35X12.50R15 tire and do not care what brand it is, just skip the BRANDS dropdown and the search will show all brands. If you know the standard size that you are doing a tire search for but not sure of the metric equivalent, skip over the METRIC WIDTH and METRIC HEIGHT drop down and just select the TIRE HEIGHT and TIRE WIDTH in inches and the search will show both the metric and standard sizes available that are close to the size tire that you are searching for.)