Perhaps you should try some spelling variations:
thue nghiem » thuc nghiem, thu nghiem, thi nghiem
sach trinh » sach tranh, hanh trinh, sach kinh
sach thue » sach thu, sach thieu, sach tham
nghiem de » nghiem d, nghiem do, nghiem te
trinh he » trinh han, trinh hoa, trinh thi
te sach » toc sach
de hoc » te hoc, dien hoc
du hoc » tu hoc, duoc hoc
he du » te du, ve du

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 thue nghiem de hoc ) or ( te sach trinh he du hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( te sach thue nghiem de hoc ) OR ( te sach trinh he du hoc )).
• Adding a wildcard symbol may retrieve word variants: (( te sach thue nghiem de hoc ) or ( te sach trinh he du hoc ))*.