"Mira que tiene cosa la mujer esta" wouldn't make sense with an accent on either words. If "que" had an accent ("qué"= what/how) it'd mean "look what/how..." and a noun, an adjective or an adverb should be the next word while "tiene" is a verb. If "esta" had an accent, it'd be the verb "estar" which indeed means "to be" but Spanish has two verbs equivalent of "to be" and "estar" in this case wouldn't make sense.


Here is the copied and pasted explanation from WordReference I linked to some posts above:
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"I'm a professional translator & the whole idea of "quality" translating is to not translate literally from 1 language to the next but to use the best "equivalent" in the receiver language, especially with colloquial phrases where word-for-word or exact translations are rarely possible.
While yes, the "idea" behind Ricky Ricardo's phrase may be "Can you believe this?!!", the more "natural" equivalent in [American] English would be as follows:

RICKY: "¡Mira que tiene cosa la mujer esta!"
ENGLISH: "How do you LIKE this woman!!!" (expressing both incredulity & exasperation)

Or the following: when in Hollywood, Ricky discovers that Lucy, Ethel & Fred have stolen John Wayne's footprints from Grauman's Chinese Theater & have hidden them under the Mertz' hotel room bed:

RICKY: "¡¡¡Mira que tiene cosa de ir al frente de Grauman's Chinese Theater y robarse los footprints de John Wayne!!!"
ENGLISH: "How do you like THAT!!! Going to the forecourt of Grauman's Chinese Theater & stealing John Wayne's footprints!!!"

You get the idea.

These translations say nothing about "can you believe it?" yet that feeling is certainly conveyed in the "very natural" & quite common American English expression of "How do you like THAT!!"

Meanwhile, Ricky Ricardo is Cuban, so this is a very common colloquial expression from Cuba. In other Spanish-speaking countries, while no doubt this phrase would for the most part be generally understood, there may be other phrases specific to each of those countries that's more "natural" to them & would be heard more frequently than Ricky's "Mira que tiene cosa...". Which would explain why the native Mexican speaker responded that he/she didn't understand this phrase."
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