Lis, the Vallejo Model Air line works well with Vallejo Airbrush Thinner #71161 or 71261 and a small (small!) amount of V's Flow Improver #71262 or 71562. Two drops of Flow Improver is usually enough for 20 to 40 drops of paint and more than three will start to noticeably slow drying time. Ammo and Lifecolor acrylic thinners should also work about the same.
The Model Color line is specifically for brush painting. Vallejo and other sources have charts that match Model Color paints to WWII camouflage colors. You can spray Model Color and all of V's other lines, but unless the one you're using says it is for spraying, you will have to thin it a lot to make it sprayable and you will absolutely have to use the Flow Improver.
About the camouflage colors themselves:
The charts for many nation's camouflage colors have changed over the years as researchers discover new information, and each chart differs in some-to-many respects from the others. Firms that make impressive claims for their charts don't always make paints that match their own charts. Look at lots of charts, read their originators' arguments, and pick one that convinces you. Then throw the other ones into a dark corner. No matter which one you choose, someone will discover a noticeable error within a few years.
About the practical aspects of choosing hobby paints:
You only have so much space and money for paint. The more eras and nationalities you build models from, the more you need to use a method that suits your personality and expectations to limit the paints you buy.
One method is to go through every paint line you can find and select this or that color from this or that line to get the best possible matches to your favorite color chart. Another method is to find one line you have the most success with and stick to that line, adjusting a color here or there if it differs uncomfortably from your preferred color chart. If you go that path, buy a bunch of empty bottles for mixing and storing and keep a log of your mixes. It's probably better not to mix more than 17ml at a time and use the common style of dropper bottles for ease of use and paint longevity.
A third method, without limit, if you like, is to decide to use Vallejo for Messerschmitt, AK for Focke-Wulf, Humbrol for Heinkel, Hataka for Dornier, &c to spice things up a bit - ignore deviations from your chart. This method takes up a lot of space. How much space do you have, and how much do you intend to spend on racks (racks are expensive!) for all those paint bottles?
I work inside our home with very limited extraction ventilation, so I avoid lacquers and enamels due to clan-up, odor, and health considerations.