強 is a character that means strong, strength, force, powerful, better, stubborn, and stiff (yes, all of this in one character).

This “strong” has less to do with physical strength and more to do with having a winning attitude, or just having the ability to win at something.

Note that most of the time, this character is pronounced “qiang” but when used with the meaning of stubborn, unyielding, or stiff, it is pronounced “jiang” in Chinese.

Also, sometimes “qiang” is used in modern Chinese to describe people that do crazy things (For example: Bicycling from Beijing to Tibet alone). I sometimes can be found outside my Beijing apartment wearing nothing but shorts and a tee-shirt while eating ice cream during a snow storm, just to hear my neighbors call me “qiang.” Maybe they mean “strong” but perhaps they are using the new meaning of “crazy strong.”

強 can also be a Chinese surname that romanizes as Jiang in the mainland or Chiang if from Taiwan.

強 is a valid Korean Hanja character with the same meaning but is mostly used in compound Korean words.

強 is used in Japanese (though normally in compound words). In Japanese, it has the same meaning but in some contexts can mean “a little more than...” or “a little over [some amount].” Most Japanese would read this as tough, strength, stiff, hard, inflexible, obstinate, or stubborn.

The variant 彊 is sometimes seen in older literature.

狂 is a single character that means “crazy” in Chinese, Japanese Kanji, and old Korean Hanja.

狂 means crazy, unrestrained, lunatic, insane, confused, deranged, wild, or mad.

This can also refer to an extreme enthusiast (like a football fan). But then, it can also refer to a person possessing a mental abnormality.

In some contexts, this can mean conceited (it probably won't be read that way on a wall scroll).

A warning: 狂 is an odd selection for a wall scroll. You should only order this if you plan to bewilder or confuse those who see it. It kind of says something about you, something that most native Asian people will not view in a good light.

While 明鏡 means mirror in Chinese, Japanese Kanji, and old Korean Hanja, it's commonly used as a metaphor for something beautiful and bright or something that provides clarity and insight.

強力 means herculean strength, powerful, or strong.

I've even heard this described as “strength to carry a mountain.”

Note: This can also be the Japanese surname Gouriki (like Mr. Strong).

共存共栄 is a Japanese proverb that means “live together and help each other,” “existing together, thriving together,” or “co-existence and co-prosperity.”