Using Multiple Relevancy Ratings for MYSQL Fulltext Search
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I am creating a website that will be used to trade certain things. As of now, the user inputs what he has to trade and what he is looking to trade for. For instance, in the case of books, the user would list that he owns a copy of the Bible and is looking for a copy of Harry Potter. The website is supposed to then find users with the highest relevancy rating between what they have and what they want. I am able to find relevancy ratings between what a user wants and what other users have. I can also find the relevancy rating for the reverse, what a user has and what other users want. However, in order to find the best match, i need to combine these two numbers and then order the resulting table according to this number. 

     $query=mysql_query("SELECT *, MATCH(their_book1, their_book2, their_book3, their_book4, their_book5, their_book6) AGAINST ('$my_trades' ) AS score1, AND MATCH(my_book1, my_book2, my_book3, my_book4, my_book5, my_book6) AGAINST ('$their_trades') AS score2  FROM $trade_table WHERE MATCH(my_book1, my_book2, my_book3, my_book4, my_book5, my_book6) AGAINST ('$their_trades') OR MATCH(their_book1, their_book2, their_book3, their_book4, their_book5, their_book6) AGAINST ('$my_trades' )") or die (mysql_error());
	

	while($row=@mysql_fetch_array($query, MYSQL_ASSOC))
	{
		echo "<br>ID: $row[user_ID]
			  score1: $row[score1]
			  score2: $row[score2]<br>";
	}

score1 and score2 represent the different relevancy ratings i need to combine.
any thoughts? Thanks 