A text queries search on the content of text fields for approximate matches to the given text search expression, {HEAD ~ e.g., the existence} of {TAIL ~ certain phrases} or word stems 
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A text queries search on the content of text fields for approximate matches to the given text search expression , { HEAD ~ e.g. , the existence } of { TAIL ~ certain phrases } or word stems
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH