Perhaps you should try some spelling variations:
thieu manh » hieu manh, tien manh, trieu minh
canh trinh » canh tranh, hanh trinh, canh tinh
thong cong » trong cong, thong thong, phong chong
hoc thieu » toc thieu, hoc hien
tong cong » trong cong, cong cong, dung cong
trinh va » trinh van, trinh vat, trinh ve
pham dat » pham dac, pham dau, pham dang
nhat » nhan

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 manh - canh trinh va ((thong cong) OR (tong cong)) san ((pham dat) or (pham nhat))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu manh - canh trinh va ((thong cong) OR (tong cong)) san ((pham dat) OR (pham nhat)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu manh - canh trinh va ((thong cong) OR (tong cong)) san ((pham dat) or (pham nhat))".
• Adding a wildcard symbol may retrieve word variants: hoc thieu manh - canh trinh va ((thong cong) OR (tong cong)) san ((pham dat) or (pham nhat))*.