Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
nam thuc » nam thuoc, am thuc, nam thu
thuc day » thuc dan, thuc vat
day hanh » day nhanh, day thanh, dao hanh
su sach » so sach
vu sach » vu bach, vu khach
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo

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) or (vu sach)) ky nang xa hoi. hieu quang nam thuc day hanh vi ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu sach)) ky nang xa hoi. hieu quang nam thuc day hanh vi ((cua tre) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (vu sach)) ky nang xa hoi. hieu quang nam thuc day hanh vi ((cua tre) or (cuu tre))*.