With 7search.com just go for broad keywords. Their volume is to way low for targeting longtails. Forget everything you learned on adwords.
The traffic from 7search converts very bad compared to a first tier PPC network. If you have something that converts 5% on google, it will convert for like 0.5% on 7search at max.
But still its possible to bank some $$ on 7search if you play smart.
1) You have to presell the visitors like crazy, directlinking to landing page is epic fail.
2) try to get as much optins as possible and blast those optins with emails EVERY DAY until they buy.
3) don't go for the highest bid (maybe only in the start to test your campaigns). Get a 2nd or 3rd spot. And because 7search does not need manual approval of ads, you can make them as crazy as needed to get the click, something like:
##### HOW I LOST 8 POUNDS in 3 DAYS [MY STORY] #####
Click Here To blabla ## ### # ### blababa A#!!!!??>?>??>?>
like nobody optimizes their title for CTR in 7search, you can dominate the competition easily
Then still if you just promote 1 product, the volume is to low to make bank. You will earn $xx per day at max.
So, if you crack the code and find a good method to scale, replicate the exact same thing in 100's of niches.
And yes, I made a few $10k's on 7search last year, its about the max you can make in there. And no i'm not going to tell you my method.