Perhaps you should try some spelling variations:
khien tinh » thien tinh, khien thich, bien tinh
truong cua » truong ca, truong quan, truong cao
nhung cong » thong cong, hang cong, nhung don
hoc khien » hoc hien, hoc nghien, hoc thieu
trung cua » trung tuan, trung cap, dung cua
dung cong » dung trong
tan khan » tan khang, tan nhan, toan khoan
khan cap » khan ap, than cap, khoan cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc khien tinh - hanh ((trung cua) or (truong cua)) ((nhung cong) OR (dung cong)) tan khan cap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc khien tinh - hanh ((trung cua) OR (truong cua)) ((nhung cong) OR (dung cong)) tan khan cap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc khien tinh - hanh ((trung cua) or (truong cua)) ((nhung cong) OR (dung cong)) tan khan cap".
• Adding a wildcard symbol may retrieve word variants: hoc khien tinh - hanh ((trung cua) or (truong cua)) ((nhung cong) OR (dung cong)) tan khan cap*.