Perhaps you should try some spelling variations:
ngoc thanh » ngoc khanh, ngoc anh, ngoc tuan
thanh hang » thanh hoang, thanh thang, tranh hang
sach hoc » cach hoc, sach hoi, mach hoc
mot ngoc » mot goc, mot ngoai, mot nguoi
hang hoa » hang khoa, thanh hoa, hang va
nhan dan » phan dau, gian dan
nhan tai » hang tai, van tai, toan tai
te sach » toc sach
cuu mot » cua mot, cuu mo, huu mot

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach hoc tap, nghien cuu mot ngoc thanh hang hoa xa hoi va ((nhan dan) OR (nhan tai))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach hoc tap, nghien cuu mot ngoc thanh hang hoa xa hoi va ((nhan dan) OR (nhan tai))".
• Adding a wildcard symbol may retrieve word variants: te sach hoc tap, nghien cuu mot ngoc thanh hang hoa xa hoi va ((nhan dan) OR (nhan tai))*.