Perhaps you should try some spelling variations:
sach tham » sach nha
tham thuc » nham thuc, pham thuc, tam thuc
thuc sinh » thuoc sinh, thu sinh, thuc kinh
sinh hoat » sinh hoc, sinh vat
pho thong » he thong
sach thai » sac thai, sach tai, sach nha
phu thong » phap thong, khau thong, phan thong
hoat pho » hoat ho, hoc pho, hoa phi
thai hoc » dai hoc, bai hoc, hoi hoc
cac khoa » cac khoan, cac khoi, dac khoa
khoa phu » khoa phau, khoa thu, hoa phu
tu sach » thu sach, su sach, te sach
hoc cac » hoc cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tu sach tham thuc sinh hoat pho thong ) or ( tu sach thai hoc cac khoa phu thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach tham thuc sinh hoat pho thong ) OR ( tu sach thai hoc cac khoa phu thong )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach tham thuc sinh hoat pho thong ) or ( tu sach thai hoc cac khoa phu thong ))*.