Multiple Columns With Different Values OR Single Column With Multiple Criteria?

Hi,

I have multiple columns in a Single Table and i want to search values in different columns. My table structure is

col1 (identity PK)
col2 (varchar(max))
col3 (varchar(max))

I have created a single FULLTEXT on col2 & col3.
suppose i want to search col2='engine' and col3='toyota' i write query as

SELECT

TBL.col2,TBL.col3
FROM

TBL
INNER JOIN

CONTAINSTABLE(TBL,col2,'engine') TBL1
ON

TBL.col1=TBL1.[key]
INNER JOIN

CONTAINSTABLE(TBL,col3,'toyota') TBL2
ON

TBL.col1=TBL2.[key]

Every thing works well if database is small. But now i have 20 million records in my database. Taking an exmaple there are 5million record with col2='engine' and only 1 record with col3='toyota', it take substantial time to find 1 record.

I was thinking this i can address this issue if i merge both columns in a Single column, but i cannot figure out what format i save it in single column that i can use query to extract correct information.
for e.g.;
i was thinking to concatinate both fields like
col4= ABengineBA + ABBToyotaBBA
and in search i use
SELECT

TBL.col4
FROM

TBL
INNER JOIN

CONTAINSTABLE(TBL,col4,' "ABengineBA" AND "ABBToyotaBBA"') TBL1
ON

TBL.col1=TBL1.[key]
Result = 1 row

But it don't work in following scenario
col4= ABengineBA + ABBCorola ToyotaBBA

SELECT

TBL.col4
FROM

TBL
INNER JOIN

CONTAINSTABLE(TBL,col4,' "ABengineBA" AND "ABB*ToyotaBBA"') TBL1
ON

TBL.col1=TBL1.[key]

Result=0 Row
Any idea how i can write second query to get result?