Perhaps you should try some spelling variations:
quan thuc » luan thuc, qua thuc, quan chuc
cau theo » cau thi, cau tao
cau treo » cau tren, cau triet, cau trieu
day manh » van manh, duc manh
ha manh » ho manh, ha anh, ha thanh
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
x hoi » xa hoi, o hoi, x ho

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 ty nang x hoi. hieu qua quan thuc ((day manh) OR (ha manh)) va ((cau treo) or (cau theo))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty nang x hoi. hieu qua quan thuc ((day manh) OR (ha manh)) va ((cau treo) OR (cau theo)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty nang x hoi. hieu qua quan thuc ((day manh) OR (ha manh)) va ((cau treo) or (cau theo))".
• Adding a wildcard symbol may retrieve word variants: su sach ty nang x hoi. hieu qua quan thuc ((day manh) OR (ha manh)) va ((cau treo) or (cau theo))*.