Perhaps you should try some spelling variations:
hien thong » vien thong, hien tuong, chien thuong
thuc cach » thuoc sach, truoc cach, thuc hanh
thi bach » thi bich, thi hanh, thi anh
sanh tri » thanh tri, dinh tri, minh tri
sach tri » sach tai, sach tren, sach truc
so sach » bo sach, co sach, hoc sach
bach va » bach van, bach ha, sach va
tri thi » tri tai, tai thi, thi thi
so sanh » do sanh
ve cach » va cach, ve cac, ve canh
va he » va che, va ghe, va de

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( so sanh tri ((thuc cach) or (ve cach)) hoc hien thong ) or ( so sach tri thi bach va he thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( so sanh tri ((thuc cach) OR (ve cach)) hoc hien thong ) OR ( so sach tri thi bach va he thong )).
• Adding a wildcard symbol may retrieve word variants: (( so sanh tri ((thuc cach) or (ve cach)) hoc hien thong ) or ( so sach tri thi bach va he thong ))*.