Perhaps you should try some spelling variations:
thong cong » trong cong, tong cong, thong thong
khien bang » phien ban, khien dong
hien sang » hien trang, chieu sang, thien bang
chinh tai » chinh tri
cong vang » cong lang, cong quang, cong ngang
chinh va » chinh ta, hanh va, tinh va
vang ban » van ban, hang ban, nang ban
ban tu » van tu

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) or (khien bang)) - hanh ((chinh va) OR (chinh tai)) thong cong vang ban tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien sang) OR (khien bang)) - hanh ((chinh va) OR (chinh tai)) thong cong vang ban tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien sang) or (khien bang)) - hanh ((chinh va) OR (chinh tai)) thong cong vang ban tu".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien sang) or (khien bang)) - hanh ((chinh va) OR (chinh tai)) thong cong vang ban tu*.