Spanish term
worked for int. orgs (IMF, OAS, IDB)
Native in: English
Works in: Spanish to English, German to English
buscan la eficacia
I wonder how we might translate "buscan la eficacia" here, bearing in mind that this is a fictitious character who is "inclinado a ajustar cuentas" and might have a personal agenda ...
Proposed translations
United Kingdom
poetically precise prose with... panache
Native in: English 
Works in: French to English, Spanish to English, English
strike home
well aimed
on the nose
carefully crafted
etc...
~~~~~
IE, they are extremely effective.
In other words, the words or actions are designed " to hit the intended place or have the intended effect " (http://dictionary.cambridge.org/dictionary/british/strike-ho...
United States
Timely Translation Turnaround
Native in: English (Variant: US)
Works in: Spanish to English, Chinese to English
seek out their intended effect
Chile
Human-scale Globalization
Native in: English (Variant: British) 
Works in: Spanish to English, French to English, English to Spanish, and 2 more.
(methods etc. which) prioritise results ...
United Kingdom
Thorough, knowledgeable and resourceful
Native in: English (Variant: UK)
Works in: French to English, Spanish to English, Italian to English, and 4 more.
in the most pertinent way / most effectively
www.coolfmjobs.co.uk/content/advertising-account-director
This is a company that believes in helping businesses to achieve their dreams and to target the desired audience in the most pertinent way possible. Their ideal ...
or even just "most effectively", depending how you phrase the rest
United Kingdom
Linguistic flair and an eye for detail
Native in: English
Works in: Spanish to English, English
rather direct
no-nonsense
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Note added at 13 hrs (2014-11-25 12:34:31 GMT)
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no-non·sense (n -n n s ns , -s ns). adj. Not tolerating irrelevancies; direct, efficient, and practical: the no-nonsense tones of a stern parent; plain, no-nonsense ...
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Note added at 13 hrs (2014-11-25 12:38:51 GMT)
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Although sometimes I wonder why I bother, as the askers often choose more lacklustre suggestions.
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Note added at 13 hrs (2014-11-25 12:40:06 GMT)
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And "no-nonsense type of guy" gets 410 hits on Google...
TRANSLATIONS THAT READ LIKE ORIGINALS
Native in: Spanish
Works in: English to Spanish, Spanish, Spanish to English, and 1 more.
without any BS
"To the point, and without any BS" is the meaning, as I understand it.
Reference comments
Jamaica
Translating the Ideas Behind the Words
Native in: English (Variant: British)
Works in: Spanish to English, English to Spanish, French to English, and 2 more.
http://forum.wordreference.com/showthread.php?t=2305514
"....methods and expressions which struggle to have the desired effect."
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