How can I use Linkedin more efficiently to find jobs in my industry?

Join a group that is specifically aligned with your industry or expertise. I am a member of Accountants in Construction, Construction Accounting, Construction Financial Management Association, among others. As you can tell I am in the construction industry, as well as an accountant. People are constantly posting job advertisements on these boards. I would venture to guess other groups are doing the same.

Linkedin recently added "Signal". This has an advanced search in which you can search by industry. To find who is hiring in your network, put "Hiring" and then position as keywords and save. i.e. if looking for marketing, use "Hiring Marketing' as the keywords. This will show you who in your network has these words.
Suggest you have multiple searches set up.

You have both "direct" and "indirect" options, both of which should expand but not relace your networking. The "direct" option should make use of "groups", and the "follow" function to follow companies and industry organizations. The "indirect" is to enhace you the brand. Key profile elements include "skills" and use of the Slideshare and Reading List applets. I encourage more experienced to sequence their profile as: Summary, Skills, Applets, history chronology, and Education.