after i built my campaign i found some impressions and only 2 clicks , but when i try to use my key words to search google , i never find my ad any explanation?
There are a number of factors that could make your ads not show including geo targeting, budget and day parting. Most likely, you have your budget set too low to have your ads always showing. Google will try to spread you spend out over the day causing your ad to NOT show every time you could potentially match a query. If you want it to show every time, up your max bid and your max budget. If you can't afford to do that, they you will just have to be patient.
There can be many reasons for your ads not showing to your own search. These reasons maybe: Ads Are Approved But Not showing to your own search 1. Your quality score or max CPC limit is too low to reduce your ad rank enough to display your ads on first page. 2. Your daily budget is either finished or is not high enough to show your ads whole day. 3. You are yourself excluded from the geolocation or language of your ad campaign (for example you target USA and your own IP is in Britain) 4. The particular keyword you are searching for is facing some problem triggering your ads. 5. It is also possible that your ads are disapproved later, but it is still showing you the old status of approved, may take upto 24 hours to update Please note that even in case of your ad running perfectly you may not see it on every single search you perform. You should run a keyword diagnosis to know whether that keyword is triggering your ads or not. If keywords are fine, then try Ad Preview And Diagnosis Tool in Tool And Analysis Tab to know the exact status of your ads for given location, domain, device and language.