Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
doi nang » dai nang, hoi nang, voi nang
hanh vin » hanh tin, hanh van, thanh vien
chat xuc » chat huu, cam xuc, chao xu
sach doi » sach hoi, sach moi, sach dao
ve chat » va chat, van chat
tu sach » thu sach, su sach, te sach
mai hoi » mai khoi, dai hoi, lai hoi
hieu ve » hieu va, hieu van
xuc va » duc va, tuc va, luc va
ma hoi » xa hoi, ma hoa, me hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach doi nang ((ma hoi) OR (mai hoi)). hieu ve chat xuc va ((hanh vin) or (hanh vi)) cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach doi nang ((ma hoi) OR (mai hoi)). hieu ve chat xuc va ((hanh vin) OR (hanh vi)) cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach doi nang ((ma hoi) OR (mai hoi)). hieu ve chat xuc va ((hanh vin) or (hanh vi)) cau tren".
• Adding a wildcard symbol may retrieve word variants: tu sach doi nang ((ma hoi) OR (mai hoi)). hieu ve chat xuc va ((hanh vin) or (hanh vi)) cau tren*.