Check if a cell full of text contains either of multiple key words

Background:

I often import large datalists from SAP into Excel to evaluate, sort and/or analyze costs.  In this data list, each row (of which there are many thousands) contains a variety of data, such as posting date, $ amount, and description of expense.  The description of expense is a text string, such as "Transmission repairs, oil chage", or "Replace tires, front brakes and rear springs".  I want to enter a formula that extract the corresponding $ amount only if the text string contains either of several specified "key words".

So Far:

After searching Excel Help, I found this example:

Check if part of a cell matches a specific text

Row  Column A

1        Data

2        Davolio

3        BD123

The example provides the Formula:   =IF(ISNUMBER(FIND("v",A2)),"OK","Not Ok")

Which checks to see if A2 contains the letter "v", which it does, so it returns the value "OK" in the target cell

My Attempt:

Lets use the following sample date for my situation:

Row  Col A             Col B          Col C

1        Date              $Amt          Description

2        22.06.2011    1,157.21    REPLACE BRAKE ROTORS/CALIPERS

3        24.06.2011    2,740.85    TRANSMISSION NOT DOWNSHIFTING

4        04.07.2011       499.80    OIL/FILTER CHANGE, TIRE ROTATION

In my case, I thought I could modify the FIND subfunction in the formula with an OR function to search a larger text string for multiple text expressions, so I tried this:

=IF(ISNUMBER(FIND(OR("BRAKE","TIRE"),A2)),B2,0)

Unfortunately, my modified formula above only returns the value "TRUE" in the target cell.  I confess, I do not understand the application of the ISNUMBER function in the use of evaluating a text string, so I really don't know where this is going wrong.

My bottom line need, is to be able to specify several "key word" text expressions, either in an OR function, or a lookup table, so that the presence of either of the keywords in the cell to be evaluated (col c) will return the corresponding dollar amount (col b) to the target cell (col D).

Would really appreciate some help.