3 phrase keywords are very good but keywords with more phrases can be very effective. Your first step is to look for keywords that are low competition but still receive plenty of searches each month regardless if it has one, two, three or more phrases in it.
Keyword is most important phrase in and that keyword tool to used with your website with related topic use it.
2-3 phrase keywords are OK for traffic and position. You should also use long tail keywords also for business, because it gives low traffic but genuine visitor
Use 2-3 phase keyword and use that keyword which more relevant and generate leads for your business. Please check that keyword search volume should be good and should have less competition.Also check your top 10 competitor in Google before targeting the keyword.