Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
thu sach » tu sach, thuoc sach, thu hoach
hieu van » hieu va, thien van, lieu va
anh giau » anh giao, canh giac, anh giang
giau cua » gian cua, gia cua, dieu cua
nang xa » nang x, lang xa, nang ma
van cac » van hac, van cau, van bac
cua tre » cua te, cuu tre, cua triet
lo van » le van, so van, do van

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) OR (thuat sach)) ky nang xa hoi. hieu van cac ((lo van) or (vo van)) anh giau cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (thuat sach)) ky nang xa hoi. hieu van cac ((lo van) OR (vo van)) anh giau cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) OR (thuat sach)) ky nang xa hoi. hieu van cac ((lo van) or (vo van)) anh giau cua tre".
• Adding a wildcard symbol may retrieve word variants: ((thu sach) OR (thuat sach)) ky nang xa hoi. hieu van cac ((lo van) or (vo van)) anh giau cua tre*.