Perhaps you should try some spelling variations:
trinh chuan » trinh quan, trinh luan, trinh phan
nhung duong » nhung dung, nhung huong, nhung tuong
thieu sang » chieu sang, thieu khang, thieu quang
duong sinh » duong minh, duong manh, trong sinh
hoc thieu » toc thieu, hoc hien
trinh han » trinh quan
sinh van » sinh vat, dinh van, sinh va

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thieu sang - canh ((trinh chuan) or (trinh han)) nhung duong sinh van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sang - canh ((trinh chuan) OR (trinh han)) nhung duong sinh van ban.
• Adding a wildcard symbol may retrieve word variants: hoc thieu sang - canh ((trinh chuan) or (trinh han)) nhung duong sinh van ban*.