Multiple if or vlookup need help

[map6122]

[TABLE="width: 500"]
<tbody>[TR]
[TD]Rule[/TD]
[TD]Born[/TD]
[TD]Trigger[/TD]
[TD]Variable[/TD]
[/TR]
[TR]
[TD]XYZ[/TD]
[TD]Texas[/TD]
[TD]Texan[/TD]
[TD]A or B or C or D[/TD]
[/TR]
[TR]
[TD]ABC[/TD]
[TD]New York[/TD]
[TD]New Yorker[/TD]
[TD]A or B or C or D[/TD]
[/TR]
[TR]
[TD]RST[/TD]
[TD][/TD]
[TD]RST[/TD]
[TD]A or B or C or D[/TD]
[/TR]
[TR]
[TD]WXY[/TD]
[TD][/TD]
[TD]WXY[/TD]
[TD]A or B or C or D[/TD]
[/TR]
[TR]
[TD]DWF[/TD]
[TD][/TD]
[TD]DWF[/TD]
[TD]A or B or C or D[/TD]
[/TR]
</tbody>[/TABLE]

Hello I need help with this excel formula. Basically I always have data in Rule column and Variable data. I want Trigger Data as a output.
I have a vlookup setup where there is Born country/data give trigger output but sometimes I do not have born data so that time I have to check Rule+Variable and get output for trigger but i want to do that only for blank Born data and I do not want override already filled Born data. I have over 60k lines of data like this.

Thanks,