Perhaps you should try some spelling variations:
"think liquid chromatography" » "thin liquid chromatography", "tank liquid chromatography", "third liquid chromatography"
"think gas chromatography" » "think fast chromatography", "think case chromatography", "think h'as chromatography"
"thin gas chromatography" » "thin glass chromatography", "thin base chromatography", "thin case chromatography"

You may be able to get more results by adjusting your search query.

• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"think gas chromatography\") OR (\"thin gas chromatography\"))) OR (\"think liquid chromatography\"))".
• Removing quotes may allow a broader search: (((( think gas chromatography ) OR ( thin gas chromatography ))) OR ( think liquid chromatography )).
• Adding a wildcard symbol may retrieve word variants: (((("think gas chromatography") OR ("thin gas chromatography"))) OR ("think liquid chromatography"))*.