• Exalead: ("tensile strength" OR "tensile stress") "fiber-reinforced" concrete
  NOTE: In Exalead, the option to limit by format is provided in a sidebar on the left side of the screen.
• Google: "corporate ethics" ("technical report" OR "white paper") (filetype:pdf OR filetype:rtf)
• Google: ("child safety seats" OR "child car seats") "seat belts" (standards OR standard OR specification) filetype:pdf
• Yahoo: ("child safety seats" OR "child car seats") "seat belts" (standards OR standard OR specification)
  NOTE: In Yahoo, as in many other search engines, you must go to the Advanced Search page to limit by filetype. You cannot do it as in Google with the filetype command. I have sometimes found that when I've just done a filetype search in Google, that Yahoo keeps those settings and limits the search to a filetype without a specific request to do so.

Tips: Basics | "1" | (2) | 3=OR | 4=site | 5=filetype | +6 | -7 | ~8 |
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