Perhaps you should try some spelling variations:
sach thanh » sach tranh, sach tham, danh thanh
sach trinh » sach tranh, hanh trinh, sach kinh
thuyet hoa » thuyet va, huyet hoc
sach danh » sach tranh, sach dao, sach dung
thuat hoa » thuat toan, thuat do, thuat o
o thuyet » hoc thuyet, ly thuyet, li thuyet
su sach » so sach, vu sach
trinh o » trinh do, trinh co, trinh mo

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( su ((sach thanh) or (sach danh)) ky thuat hoa hoc ) or ( su sach trinh o thuyet hoa hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( su ((sach thanh) OR (sach danh)) ky thuat hoa hoc ) OR ( su sach trinh o thuyet hoa hoc )).
• Adding a wildcard symbol may retrieve word variants: (( su ((sach thanh) or (sach danh)) ky thuat hoa hoc ) or ( su sach trinh o thuyet hoa hoc ))*.