There are a number of keywords that a company providing web design services might use when advertising on Google. Some examples include:

1. "Web design agency"
2. "Professional web design"
3. "Custom web design"
4. "Responsive web design"
5. "E-commerce web design"
6. "Small business web design"
7. "Website redesign"
8. "WordPress web design"
9. "Web design services"
10. "Affordable web design"

In addition to these keywords, it may also be helpful to include location-specific keywords, such as the name of the city or region where the company is based. For example, a company based in New York City might include the keyword "NYC web design" in its advertising.
It can be helpful to use a combination of broad and specific keywords to reach a wide range of potential clients. It may also be helpful to use tools such as the Google Ads Keyword Planner to research and identify relevant keywords for your business.