Perhaps you should try some spelling variations:
trinh quan » tinh quang, trinh luat, trinh han
khong cang » thong cong, hong bang, khong dung
hien sang » hien trang, khien bang, chieu sang
trinh cua » tinh cua, trinh luat, trinh luan
cang cao » nang cao, cong cao, lang cao
chat van » chat va, chat ban, chat ran

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hien sang - hanh ((trinh cua) OR (trinh quan)) khong cang cao chat van~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hien sang - hanh ((trinh cua) OR (trinh quan)) khong cang cao chat van".
• Adding a wildcard symbol may retrieve word variants: hoc hien sang - hanh ((trinh cua) OR (trinh quan)) khong cang cao chat van*.