Gift.php

if ( $this->getRequest()->getPost( 'age' ) ) {
			$value = $this->getRequest()->getPost( 'age' );
			$split_age = explode( '-', $value );
			$age_array = [];
			foreach($split_age as $age){
					$age_array[] = array( 'finset' => array( $age ) );
			}

		}

		// Filter the sex
		$sex = $this->getRequest()->getPost( 'sex' );

		if ( $sex == 'Unisex' ) {
			$sex_array = array(
				array( 'attribute' => 'Sex', 'eq' => 'Mens' ),
				array( 'attribute' => 'Sex', 'eq' => 'Womens' ),
				array( 'attribute' => 'Sex', 'eq' => 'Unisex' ),
			);
		} elseif ( $sex == 'Mens' ) {
			$sex_array = array(
				array( 'attribute' => 'Sex', 'eq' => 'Mens' ),
				array( 'attribute' => 'Sex', 'eq' => 'Unisex' ),
			);
		} else {
			$sex_array = array(
				array( 'attribute' => 'Sex', 'eq' => 'Womens' ),
				array( 'attribute' => 'Sex', 'eq' => 'Unisex' )
			);
		}


		$_products = Mage::getModel( 'catalog/product' )->getCollection()
		                 ->addAttributeToSelect( '*' )
		                 ->addAttributeToFilter( 'Sex', $sex_array )
		                 ->addAttributeToFilter('activity', array("finset"=> $this->getRequest()->getPost('activity')))
                         ->addAttributeToFilter( 'age', $age_array);