Perhaps you should try some spelling variations:
thanh truc » thanh trung, thanh tra, hang truc
su sach » so sach, vu sach
cuu tre » cua tre, cau tren, cau treo
danh va » doanh va, hanh va, anh va
va danh » va dinh, va dan, va hanh
lang xa » lang ha, dang xay, lang van
cu tren » tu tren, dua tren
sach o » sach lo, sac o, sach y
o lang » hoa lang, hoi lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach o lang xa hoi. hieu qua ((thanh truc) OR (thanh thuy)) va danh va ((cuu tre) or (cu tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach o lang xa hoi. hieu qua ((thanh truc) OR (thanh thuy)) va danh va ((cuu tre) OR (cu tren))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach o lang xa hoi. hieu qua ((thanh truc) OR (thanh thuy)) va danh va ((cuu tre) or (cu tren))*".