SQL QUERY FOR LISTBOX

[amitbadgi]

Hi guys I have created a form in access which has 4 options,
BID, Telephone, address and License number, now if a employee enters
any one of the fields and clicks search, the related record is pulled
out, and there are 2 differnet cities which have 2 tables each. Here is
teh query that I have written

SELECT OneWorld.bus_id, OneWorld.bus_nam, OneWorld.bus_add,
OneWorld.city, OneWorld.state, OneWorld.zip, OneWorld.phone,
OneWorld.license
FROM [Select Distinct dbo_businessNC.bus_id as
bus_id,dbo_businessNC.bus_name as bus_nam,dbo_businessNC.adrs1 as
bus_add,dbo_businessNC.city as city,dbo_businessNC.state as
state,dbo_businessNC.zip as zip, dbo_businessNC.phone as phone,
dbo_occhistoryNC.license as license from dbo_businessNC,
dbo_occhistoryNC WHERE ( dbo_businessNC.bus_id=dbo_occhistoryNC.bus_id)
UNION ALL Select bus_id, bus_name as bus_nam, bus_add, city, state,
zip, phone, license from Hawaccsumm
]. AS OneWorld
WHERE (((OneWorld.bus_id) LIKE "*" &[Forms].[Form1].[Text2]& "*")) AND
(((OneWorld.bus_nam) LIKE "*" &[Forms].[Form1].[Text5]& "*")) AND
(((OneWorld.bus_add) LIKE"*" & [Forms].[Form1].[Text8]& "*")) AND
(((OneWorld.phone) LIKE "*" &[Forms].[Form1].[Text10]& "*")) AND
(((OneWorld.zip) LIKE "*" &[Forms].[Form1].[Text15]& "*"));

Now I want to include a listbox with 3 options
city1, city2, all
Hence if the user selects city1 and then enters a field and clicks
search, then only city1 shld be searched and teh related record shld be
pulled out, and the same for city 2, and for ALL, all teh cities shld
be searched, which its doign as of now. Hence i wanted to know how do i
proceed. Thanks.