Lack of light, too much dust or very little water is few issues that can destroy the indoor plants. Here are simple ways on how to get them back in shape:
With the help of small hand cultivator, you can grate the first few inches of the soil surface. Try it for the larger pots. The idea is to move around the soil and reinvigorate it, as well as remove dry crust. Be careful it should not damage the roots, which are soft and fragile in majority of the cases like clivia plants. If the water that you need for the plants is calcareous, it is possible a whitish crust will be seen on the surface. You need to remove it first. Add mineral and organic mulch around the plants, which keeps it healthy.
Use sponge with de-ionized water to wash the large shiny leaves. Never go for a polishing product. The priority always remains the upper leaves, as it will have most of the dust and dirt. Rinse a sponge every other leaf at least. You don’t need to wash with a dirty sponge, as it would penetrate deeper. You can even shower the plant with lukewarm water, which is the best idea for indoor plants.
Remove the withering stems
When a plant receives little or no light, it produces thinner internodes that elongate between the leaves. The newly formed leaves are smaller than others. Shorten the stems and taper them to a particular leave where the leaves appear to be normal or large enough.
Indoor vines like cissus, scindapsus are sensitive to the withering phenomenon. If the plant develops thinner stems, then it needs additional light. Consider moving the plants close to the window.