Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
nam truc » nam truoc, nam thuc, nam trung
dau tren » dau tien, dat tren, dau tieng
su sach » so sach, vu sach
ky lang » ky nang, ky dang, tay lang
ky tang » ky nang, ky dang, kho tang
truc va » thuc va, thuc vat, trung va
va hang » van hang, va nang, va lang
va dau » va dao

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 ((ky lang) OR (ky tang)) xa hoi. hieu quang nam truc va hang va dau tren~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ky lang) OR (ky tang)) xa hoi. hieu quang nam truc va hang va dau tren".
• Adding a wildcard symbol may retrieve word variants: su sach ((ky lang) OR (ky tang)) xa hoi. hieu quang nam truc va hang va dau tren*.