Perhaps you should try some spelling variations:
thong tinh » thuong tinh, thong tin, thong minh
phong minh » thong minh, khong minh, phong tinh
can thong » ban thong, van thong, chan thuong
van phong » van dong, hai phong
sach bac » sach bai, sach dao, sach xa
giai van » gioi van, giai han, giai san
sach cha » sach nha, sach che, sach ha
giai can » giai han, giai san, giai ca
me giai » de giai, ke giai, le giai
sach ba » sach bai, sach bao, sach xa
ve giai » va giai, ve giao, de giai
tu sach » thu sach, su sach, te sach
cha ve » cha me, ca ve, pha ve

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 ba) or (sach bac)) me giai van phong minh ) or ( tu sach cha ve giai can thong tinh ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu ((sach ba) OR (sach bac)) me giai van phong minh ) OR ( tu sach cha ve giai can thong tinh )).
• Adding a wildcard symbol may retrieve word variants: (( tu ((sach ba) or (sach bac)) me giai van phong minh ) or ( tu sach cha ve giai can thong tinh ))*.