Im pretty new and i had bought a spartial scanner , every container i open theres no blue print . is there any location where i can find them?
Unfortunately, Mysterious Container contain random item. Blueprints are less common than 100k, 300k 1mil creds or crafting materials and after those some blueprints appear more often than others (pirate modules, that even sold are worth almost nothing).
Some places are better than others for looting and unfortunately I am not sure about Mysterious containers as how many drop in a sector and how often but a great guide to REALLY help is :
If you take the time to read all of it then it can save you a lot of time and headache… Some of these methods helped me to max all of the standard ships in a very short time which is why all my ships are maxed. Doing it the way I was before was a brutal grind. 
And no I am not advertising for ORCA1911 lol just trying to help and pay it forward like he did for me along with many others.
Spatial scanner is now semi-useless unless you plan on spending hours on end in open space. The “mysterious containers” which rarely contain blueprints are scatters to the edges of maps and are nearly impossible to find even with the scanner.