Perhaps you should try some spelling variations:
canh trinh » canh tranh, hanh trinh, canh tinh
sach ngan » sach ngon, sach nha, sach han
toc sach » hoc sach, doc sach, thuoc sach
ngan hoc » nhan hoc, nganh hoa, nganh soc
hoc khia » hoc khoa, hoc chia, hoc khi
hoa thi » hoa thai, hoa phi, hoa hi
ha thi » pham thi

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( toc sach ngan hoc khia đong luc ) or ( luc canh trinh ((hoa thi) OR (ha thi)) đong luc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( toc sach ngan hoc khia đong luc ) OR ( luc canh trinh ((hoa thi) OR (ha thi)) đong luc )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( toc sach ngan hoc khia đong luc ) or ( luc canh trinh ((hoa thi) OR (ha thi)) đong luc ))".
• Adding a wildcard symbol may retrieve word variants: (( toc sach ngan hoc khia đong luc ) or ( luc canh trinh ((hoa thi) OR (ha thi)) đong luc ))*.