Perhaps you should try some spelling variations:
trinh thiet » trinh viet, trinh thi
sach trinh » sach tranh, hanh trinh, sach kinh
te thanh » tre thanh, le thanh, de thanh
thiet de » thiet ke, nhiet de, thiet yeu
te hanh » tu hanh, ve hanh, te danh
tu sach » thu sach, su sach, te sach
tu hoc » te hoc
de hoc » te hoc, du hoc, dien hoc
dien » bien, vien, tien

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( ((te hanh) OR (te thanh)) tinh dien tu hoc ) or ( tu sach trinh thiet de hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( ((te hanh) OR (te thanh)) tinh dien tu hoc ) OR ( tu sach trinh thiet de hoc )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( ((te hanh) OR (te thanh)) tinh dien tu hoc ) or ( tu sach trinh thiet de hoc ))".
• Adding a wildcard symbol may retrieve word variants: (( ((te hanh) OR (te thanh)) tinh dien tu hoc ) or ( tu sach trinh thiet de hoc ))*.