[Does so]

I snack on Metamucil crackers. Do they contain soluble fiber?

(The right “stuff”?).

[ConservativeMind]

Those have psyllium and oat fiber, which are two helpful soluble fiber forms.

Consider adding sources that have a blend of other fibers.

Sola Bread has resistant wheat starch, oat fiber, citrus fiber, flaxseed fiber, and a vegetable fiber blend that further includes pea, potato, bamboo shoot and guar gum fiber.

Catalina Crunch is a crunchy snack that has potato, corn, inulin, and guar gum fiber sources.

It is helpful to get a variety of soluble fiber sources, because different gut bacteria can create more useful substances. It is also possible we don't have gut bacteria another has, so one form of fiber may not get utilized well, or you actually needed a different fiber, instead.