Perhaps you should try some spelling variations:
vu sach » vu bach, su sach, vu khach
hanh de » hanh ve, hanh kem
cam luc » cam xuc, cau luc
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
le lang » le tang, le dang, le xang
lo lang » o lang, so lang, hoa lang
luc va » duc va, tuc va, loc va
ve cam » ve cham, ve cac, va cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ((lo lang) OR (le lang)) xa hoi. hieu ve cam luc va ((hanh vi) or (hanh de)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ((lo lang) OR (le lang)) xa hoi. hieu ve cam luc va ((hanh vi) OR (hanh de)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ((lo lang) OR (le lang)) xa hoi. hieu ve cam luc va ((hanh vi) or (hanh de)) cua tre".
• Adding a wildcard symbol may retrieve word variants: vu sach ((lo lang) OR (le lang)) xa hoi. hieu ve cam luc va ((hanh vi) or (hanh de)) cua tre*.