Nonny, you’re in the right place. :)
You can charge a charm, crystal, or talisman for any purpose you wish, and that includes assigning multiple intents.
For example, I have a house blessing charm made from a coconut shell that has at least ten different purposes, each assigned to a different substance that I put into the shell when it was made.
All of my powders have ingredients with multiple intents that combine into a single purpose. Usually, this includes one or two for the main purpose (banishing evil spirits, protection during travel, etc.), one or two that support the main purpose in a nonspecific way (cleansing, general protection, warding against harm, etc.), and at least one intended to boost the power of the whole mix.
Mind you, this is my own craft, which relies strongly on my own focus and the power of plants. Charging crystals and such is slightly different, but the basic process is still the same.
If you feel the need to put multiple intents into a charm, it’s completely doable. Just make sure that your intentions are clear from the get-go, be very specific with what you want the charm to do, and really focus if you’re charging the item with your own energy.