The keyword group option allows you to set up monitoring searches that require combinations of search terms without having to create multiple topics for the different variations.
The below demonstrates an example of how a multiple combination search can be built in to a single topic.
British Airways AND Strike OR dispute OR walkout
British Airlines Association AND Strike OR dispute OR walkout
BALPA AND Strike OR dispute OR walkout
The above can be constructed into a single topic using the keyword group option (see below) this method will not require you to create 3 individual topics for the different variations, but can rather be done into a single topic as per below.