Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
sach thu » sach thue, sach thieu, sach tham
thu nang » thi nang, thu hang, thu bang
nang xa » nang x, lang xa, nang ma
van cam » van lam, van cau, van dam
danh vi » dinh vi, danh di, danh va
cu tren » tu tren, dua tren
xuc va » duc va, tuc va, luc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach thu nang xa hoi. hieu ((van cam) OR (van nam)) xuc va ((danh vi) or (hanh vi)) cu tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach thu nang xa hoi. hieu ((van cam) OR (van nam)) xuc va ((danh vi) OR (hanh vi)) cu tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach thu nang xa hoi. hieu ((van cam) OR (van nam)) xuc va ((danh vi) or (hanh vi)) cu tren".
• Adding a wildcard symbol may retrieve word variants: thu sach thu nang xa hoi. hieu ((van cam) OR (van nam)) xuc va ((danh vi) or (hanh vi)) cu tren*.