Perhaps you should try some spelling variations:
thieu khang » chieu khong, thieu quang
nhung cong » dung cong, thong cong, hang cong
hoc thieu » toc thieu, hoc hien
trinh cua » trinh luat, trinh quan, trinh luan
trinh san » trinh han, trinh quan, trinh toan
tinh cua » sinh cua, tinh chat, tranh cua
sinh va » sinh vat, tinh va, dinh van
san cau » van cau, ban cau, can cau

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: hoc thieu khang - hanh ((((tinh cua) OR (trinh cua))) OR (sinh va)) nhung cong trinh san cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu khang - hanh ((((tinh cua) OR (trinh cua))) or (sinh va)) nhung cong trinh san cau~".
• Adding a wildcard symbol may retrieve word variants: hoc thieu khang - hanh ((((tinh cua) OR (trinh cua))) or (sinh va)) nhung cong trinh san cau*.