Perhaps you should try some spelling variations:
peptide chromatography » preparative chromatography, liquid chromatography, fluid chromatography
think peptide » thiol peptides, chain peptide, hinge peptide
link gas » link goes, link a, link ads

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (( link gas chromatography ) OR ( think peptide chromatography )).
• Adding a wildcard symbol may retrieve word variants: (( link gas chromatography ) or ( think peptide chromatography ))*.