You probably just want to change all of the"OR" references to "AND" in these lines:
$WADbSearch1->addComparisonFromEdit("title1","Equipment","OR","=",0);
$WADbSearch1->addComparisonFromEdit("title2","Industry","OR","=",0);
$WADbSearch1->addComparisonFromEdit("title3","Application","OR","=",0);
$WADbSearch1->addComparisonFromEdit("title4","Process","OR","=",0);