List where you can select multiple values?

Hello,
To explain what we are trying to do as simply as possible:
We want to create a list of various suppliers contact details. In one cell per row, we would like to be able to create a 'list' of categories (ie. Landscapers, Carpenters, Builders, Earthmovers, etc) where we can select MULTIPLE valves (ie. Landscaper and Earthmover) and we want to be able to then filter that information to display only 'landscapers' etc....

Is there a way to create a 'list' (ie. drop down or similar?) where you can 'select' the multiple valves for ONE cell?

Is there a way to be able to do this? (FYI. We know how to filter etc, we're just looking for guidance on the multiple valve lists)

THANK YOU IN ADVANCE

Thank you, I'll try wording it in another way.

Company "ABC" is a subcontractor who we want to keep on an Excel Register. One of the columns is "Services Provided" where we have we have used a data validation list to list all the services our subcontractors provide. However "ABC" company do "Steel Work" as well as "Landscaping". We want to be able to select BOTH those services from the list, so that when we filter the list on 'Services Provided" column they will appear on both the "Steel work" and "Landscaping" list.
We don't want to have to do with this MANY columns, we want it to all be in one.

Does that help explain what I'm trying to do better?