Why wont the OR Function Work in this Formula?

[bearwires]

I've tried to make this formula more concise using the OR function, but it doesnt need to like it.
Have I done something wrong?
Any ideas how to make it work?

Before OR Function (Works):

=IF(ISNUMBER(SEARCH("M&E",D$41)),"Electrical & Mechanical",IF(ISNUMBER(SEARCH("Electrical",D$41)),"Electrical",IF(ISNUMBER(SEARCH("Fire Alarm",D$41)),"Electrical",IF(ISNUMBER(SEARCH("Mechanical",D$41)),"Mechanical",IF(ISNUMBER(SEARCH("Plumbing",D$41)),"Mechanical",IF(ISNUMBER(SEARCH("AC",D$41)),"Mechanical",IF(ISNUMBER(SEARCH("Ventilation",D$41)),"Mechanical",IF(ISNUMBER(SEARCH("Ductwork",D$41)),"Mechanical",IF(ISNUMBER(SEARCH("Temps",D$41)),"Electrical & Mechanical",IF(ISNUMBER(SEARCH("Pull Testing",D$41)),"Electrical & Mechanical",IF(ISNUMBER(SEARCH("Pipework",D$41)),"Mechanical",IF(ISNUMBER(SEARCH("Pump",D$41)),"Mechanical",IF(ISNUMBER(SEARCH("AHU",D$41)),"Mechanical",IF(ISNUMBER(SEARCH("Chiller",D$41)),"Mechanical",IF(ISNUMBER(SEARCH("BMS",D$41)),"Mechanical",IF(ISNUMBER(SEARCH("SPARE",D$41)),"TBC-GIVE MS A NAME","NAME RA CORRECTLY"))))))))))))))))

With OR Function (Don't Work):

=IF(ISNUMBER(SEARCH(OR("M&E","Temps","Pull Testing"),D$41)),"Electrical & Mechanical",IF(ISNUMBER(SEARCH(OR("Electrical","Fire Alarm"),D$41)),"Electrical",IF(ISNUMBER(SEARCH(OR("Mechanical","Plumbing","AC","Ventilation","Ductwork","Pump","AHU","Chiller","BMS"),D$41)),IF(ISNUMBER(SEARCH("SPARE",D$41)),"TBC-GIVE MS A NAME","NAME RA CORRECTLY"))))

 

[Fluff]

Are the phrases like M&E, Temps etc the only contents of the cell, or are they part of larger strings?

 

[RoryA]

You can use this syntax::

=IF(COUNT(SEARCH({"M&E","Temps","Pull Testing"},D$41)),"Electrical & Mechanical",

...etc

 

[bearwires]

Are the phrases like M&E, Temps etc the only contents of the cell, or are they part of larger strings?

The cell rely on manual input so I would like the formula to accommodate larger text strings including those words if possible. For example, if I typed “Temps - Lighting”, I’d like the formula to result in “Electrical” or if I typed “Temps - AC”, it should be “Mechanical” result.

 

[Fluff]

Ok, you can either do it as Rory has shown, or another option is like

=IF(SUM(COUNTIFS(D$41,{*"M&E*","*Temps*","*Pull Testing*"})),"Electrical & Mechanical",IF(SUM(COUNTIFS(D$41,{"*Electrical*","*Fire Alarm*"})),"Electrical"

 

[bearwires]

Ok, you can either do it as Rory has shown, or another option is like

=IF(SUM(COUNTIFS(D$41,{*"M&E*","*Temps*","*Pull Testing*"})),"Electrical & Mechanical",IF(SUM(COUNTIFS(D$41,{"*Electrical*","*Fire Alarm*"})),"Electrical"

Thanks Fluff, it works great.
Rory's solution also works but I cant mark both as a solution.

 

[Fluff]

Glad we could help & thanks for the feedback.