Perhaps you should try some spelling variations:
"white space communications direct" » "white space communication trust" (Expand Search), "white space communications via" (Expand Search), "white space communication device" (Expand Search), "white space communication direct" (Expand Search), "white rate communications direct" (Expand Search), "white voice communications direct" (Expand Search), "white spruce communications direct" (Expand Search)
"white burst communications direct" » "white burst communication trust" (Expand Search), "white burst communications via" (Expand Search), "white burst communication device" (Expand Search), "white rural communication direct" (Expand Search), "white b communications direct" (Expand Search), "white bfsk communication direct" (Expand Search), "white forest communications direct" (Expand Search)

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• Performing a fuzzy search may retrieve terms with similar spellings: (("white space communications direct") OR ("white burst communications direct"))~.
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• Removing quotes may allow a broader search: (( white space communications direct ) OR ( white burst communications direct )).
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