Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
tru nang » tra nang, tri nang, truc nano
hieu van » hieu va, thien van, lieu va
ban hanh » ban hang
cua viet » ca viet, hoa viet, cua vat
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
nam cau » nam cao, nam cac, nam ca
cau ban » can ban, cac ban, cuu ban
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: ((thu sach) or (su sach)) tru nang xa hoi. hieu van nam cau ban hanh vi ((cua tre) or (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (su sach)) tru nang xa hoi. hieu van nam cau ban hanh vi ((cua tre) OR (cua viet)).
• Adding a wildcard symbol may retrieve word variants: ((thu sach) or (su sach)) tru nang xa hoi. hieu van nam cau ban hanh vi ((cua tre) or (cua viet))*.