Perhaps you should try some spelling variations:
bell testing » self testing, seed testing, soil testing
liang liang » liang liying, wang liang, liang ying
testing can » testing chain, testing a, testing cpt
lian xiang » li xiang
can bell » can tell, jan bell, can spell
case im » case i, case ii, case iii
case iv » case i, case ii, phase iv

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

• Performing a fuzzy search may retrieve terms with similar spellings: wang ((liang liang) or (lian xiang)) can bell testing can ((case im) OR (case iv)) ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: wang ((liang liang) OR (lian xiang)) can bell testing can ((case im) OR (case iv)) ;*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wang ((liang liang) or (lian xiang)) can bell testing can ((case im) OR (case iv)) ;*".