Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
tru nang » tra nang, tri nang, truc nano
luc van » luoc van, luu van, luc va
duc van » duc va, duc tan, duc manh
hieu ve » hieu va, hieu van
tu nang » tu nong, tu nano, tu lang
cua tre » cua te, cuu tre, cua triet
ve cam » ve cham, ve cac, va cam
vi cua » vai cua, di cua

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 ((tu nang) OR (tru nang)) xa hoi. hieu ve cam ((duc van) or (luc van)) hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((tu nang) OR (tru nang)) xa hoi. hieu ve cam ((duc van) OR (luc van)) hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((tu nang) OR (tru nang)) xa hoi. hieu ve cam ((duc van) or (luc van)) hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ((tu nang) OR (tru nang)) xa hoi. hieu ve cam ((duc van) or (luc van)) hanh vi cua tre*.