Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
thu nang » thi nang, thu hang, thu bang
cua viet » ca viet, hoa viet, cua vat
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
ve cham » va cham, ve chat, vu cham
duc van » duc tan, duc manh, duc phan
cua tre » cua te, cuu tre, cua triet

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 thu nang xa hoi. hieu ve cham ((duc van) or (duc va)) hanh vi ((cua tre) or (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach thu nang xa hoi. hieu ve cham ((duc van) OR (duc va)) hanh vi ((cua tre) OR (cua viet)).
• Adding a wildcard symbol may retrieve word variants: tu sach thu nang xa hoi. hieu ve cham ((duc van) or (duc va)) hanh vi ((cua tre) or (cua viet))*.